feat: completions API improvements, gemini endpoint, response types

This commit is contained in:
Nikketryhard
2026-02-15 17:08:53 -06:00
parent afa96b88a5
commit ca9f808ee3
8 changed files with 1031 additions and 742 deletions

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@@ -47,17 +47,18 @@ sudo ./scripts/mitm-redirect.sh status # check current state
## Endpoints
| Method | Path | Description |
| -------- | ---------------------- | ----------------------------------------------------------- |
| `POST` | `/v1/responses` | **Responses API** (primary) — supports `stream: true/false` |
| `POST` | `/v1/chat/completions` | Chat Completions API (OpenAI compat shim) |
| `GET` | `/v1/models` | List available models |
| `GET` | `/v1/sessions` | List active sessions |
| `DELETE` | `/v1/sessions/:id` | Delete a session |
| `POST` | `/v1/token` | Set OAuth token at runtime |
| `GET` | `/v1/usage` | MITM-intercepted token usage stats |
| `GET` | `/v1/quota` | LS quota — credits, per-model rate limits, reset timers |
| `GET` | `/health` | Health check |
| Method | Path | Description |
| ---------- | ---------------------- | ----------------------------------------------------------- |
| `POST` | `/v1/responses` | **Responses API** (primary) — supports `stream: true/false` |
| `POST` | `/v1/chat/completions` | Chat Completions API (OpenAI compat shim) |
| `GET/POST` | `/v1/search` | **Web Search** — Google Search grounding, returns results |
| `GET` | `/v1/models` | List available models |
| `GET` | `/v1/sessions` | List active sessions |
| `DELETE` | `/v1/sessions/:id` | Delete a session |
| `POST` | `/v1/token` | Set OAuth token at runtime |
| `GET` | `/v1/usage` | MITM-intercepted token usage stats |
| `GET` | `/v1/quota` | LS quota — credits, per-model rate limits, reset timers |
| `GET` | `/health` | Health check |
## Available Models
@@ -116,8 +117,8 @@ curl -s http://localhost:8741/v1/responses \
}' | jq .
# Follow-up in same cascade:
curl -s http://localhost:8741/v1/responses \
-H "Content-Type: application/json" \
curl -s http://localhost:8741/v1/responses \\
-H "Content-Type: application/json" \\
-d '{
"model": "gemini-3-flash",
"input": "Now multiply that by 10",
@@ -126,6 +127,64 @@ curl -s http://localhost:8741/v1/responses \
}' | jq .
```
## Web Search
The proxy supports Google Search grounding in two ways:
### 1. Dedicated Search Endpoint (`/v1/search`)
Returns structured search results with citations:
```bash
# Quick GET search
curl -s 'http://localhost:8741/v1/search?q=latest+rust+news' | jq .
# Full POST search with options
curl -s http://localhost:8741/v1/search \\
-H "Content-Type: application/json" \\
-d '{
"query": "latest Rust programming news",
"model": "gemini-3-flash",
"timeout": 30
}' | jq .
```
Response includes `summary`, `results[]` (title + URL), `citations[]`, and raw `grounding_metadata`.
### 2. Inline Grounding (on any endpoint)
Enable Google Search grounding on regular requests:
```bash
# Completions API
curl -s http://localhost:8741/v1/chat/completions \\
-H "Content-Type: application/json" \\
-d '{
"model": "gemini-3-flash",
"messages": [{"role": "user", "content": "What happened in tech today?"}],
"web_search": true
}' | jq .
# Responses API (OpenAI-style tool)
curl -s http://localhost:8741/v1/responses \\
-H "Content-Type: application/json" \\
-d '{
"model": "gemini-3-flash",
"input": "What happened in tech today?",
"tools": [{"type": "web_search_preview"}],
"stream": false
}' | jq .
# Gemini API
curl -s http://localhost:8741/v1/gemini \\
-H "Content-Type: application/json" \\
-d '{
"model": "gemini-3-flash",
"message": "What happened in tech today?",
"google_search": true
}' | jq .
```
## Authentication
The proxy needs an OAuth token. Three ways to provide it:

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@@ -1,464 +1,128 @@
# Endpoint Gap Analysis
> **Generated:** 2026-02-15 (updated)
> **Proxy Version:** 3.1.0
> **Scope:** All three API endpoints vs official OpenAI / Gemini specifications
> **Updated:** 2026-02-15
> **Sources:** [OpenAI Chat Completions API](https://platform.openai.com/docs/api-reference/chat/create), [OpenAI Responses API](https://platform.openai.com/docs/api-reference/responses), [Gemini Thinking Mode](https://ai.google.dev/gemini-api/docs/thinking-mode), proxy source code
> **Method:** Full source audit cross-referenced against context7 OpenAI API docs
---
## Table of Contents
## What's Implemented
- [Endpoint Overview](#endpoint-overview)
- [Feature Parity Matrix](#feature-parity-matrix)
- [Detailed Endpoint Analysis](#detailed-endpoint-analysis)
- [Responses API (`/v1/responses`)](#responses-api-v1responses)
- [Chat Completions API (`/v1/chat/completions`)](#chat-completions-api-v1chatcompletions)
- [Gemini API (`/v1/gemini`)](#gemini-api-v1gemini)
- [Priority Gaps](#priority-gaps)
- [Architecture Notes](#architecture-notes)
### All Endpoints
- ✅ Sync + streaming modes
- ✅ Model selection + validation
- ✅ OAuth auth check
- ✅ Timeout control
- ✅ Tool definitions, tool choice, tool results (OpenAI → Gemini auto-conversion)
- ✅ MITM bypass path for custom tools
- ✅ Thinking/reasoning in both sync and streaming
- ✅ Generation params forwarded via MITM (`temperature`, `top_p`, `top_k`, `max_output_tokens`, `stop_sequences`, `frequency_penalty`, `presence_penalty`)
-`reasoning_effort` / `thinkingLevel` — forwarded as `generationConfig.thinkingConfig.thinkingLevel`
-`response_format: {type: "json_object"}` — injected as `responseMimeType: "application/json"`
- ✅ Google Search grounding — `web_search: true` (Completions), `tools: [{type: "web_search_preview"}]` (Responses), `google_search: true` (Gemini)
-`/v1/search` endpoint — dedicated web search via Google Search grounding, returns structured results + citations
### Reasoning Effort → Thinking Level Mapping
| OpenAI `reasoning_effort` | Google `thinkingLevel` | Gemini 3 Pro | Gemini 3 Flash |
| :-----------------------: | :--------------------: | :----------: | :------------: |
| `"low"` | `"low"` | ✅ | ✅ |
| `"medium"` | `"medium"` | ❌ | ✅ |
| `"high"` | `"high"` | ✅ (default) | ✅ (default) |
| — | `"minimal"` | ❌ | ✅ |
### Completions-Specific
-`stream_options.include_usage` — final chunk with usage before `[DONE]`
-`completion_tokens_details.reasoning_tokens` — thinking token count
-`prompt_tokens_details.cached_tokens` — cache read tokens
-`temperature`, `top_p`, `max_tokens`, `max_completion_tokens`, `frequency_penalty`, `presence_penalty`
-`reasoning_effort`
-`stop` — string or array, forwarded as `generationConfig.stopSequences`
-`response_format: {type: "json_object"}` — injects `responseMimeType`
-`response_format: {type: "json_schema", json_schema: {...}}` — injects `responseMimeType` + `responseSchema` via MITM
-`n` (multiple choices) — fires N parallel cascades, collects into `choices[]` (sync only, capped at 5)
-`conversation` — session ID for multi-turn cascade reuse (custom extension)
-`reasoning_content` — thinking text in assistant message
-`system_fingerprint``fp_<version>` in sync + all streaming chunks
-`service_tier``"default"` in sync + all streaming chunks
-`logprobs: null` — in every choice (sync + streaming)
-`metadata` — accepted in request, ignored
-`finish_reason` — correctly maps Google's `MAX_TOKENS``"length"`, `SAFETY``"content_filter"`, etc.
- ✅ Full `messages[]` history — all user, assistant, system, tool messages forwarded
### Responses-Specific
- ✅ Full streaming event set (all `response.*` events including reasoning summary)
-`temperature`, `top_p`, `max_output_tokens`
-`reasoning_effort` — echoed from client request
-`thinking_signature` for multi-turn thinking chains
-`instructions`, `metadata`, `user` — echoed in response
- ✅ Usage with MITM-intercepted real tokens
-`max_tool_calls` — limits tool calls returned per response
-`conversation` — session reuse
-`previous_response_id`, `store`, `parallel_tool_calls`, `truncation`, `text.format`, `tool_choice` — echoed
-`tools` — echoed from client request (was previously always `[]`)
-`text.format``{format: {type: "json_schema", ...}}` injects `responseMimeType` + `responseSchema` via MITM, echoed in response
### Gemini-Specific
- ✅ Native tool format (no conversion needed)
-`usageMetadata` in sync **and streaming** responses
-`temperature`, `topP`, `topK`, `maxOutputTokens`, `stopSequences`
-`thinkingLevel`
- ✅ Session/conversation reuse
- ✅ Array/multipart `input` — strings, string arrays, `{text: "..."}` object arrays
---
## Endpoint Overview
## Fixed Bugs
The proxy exposes three main API endpoints, each serving different client ecosystems:
| # | Bug | Fix |
| --- | -------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------- |
| B1 | Messages history dropped | `extract_chat_input` now calls `build_conversation_with_tools` with ALL messages — full multi-turn via `messages[]` works. |
| B2 | `finish_reason` never `"length"` | `google_to_openai_finish_reason()` helper maps `MAX_TOKENS``"length"`, `SAFETY`/`RECITATION`/etc→`"content_filter"`. Applied to all paths. |
| B3 | `reasoning` always null | `build_response_object` now echoes client's `reasoning_effort` from `RequestParams`. |
| B4 | `tool_choice` always `"auto"` | Changed from `&'static str` to `serde_json::Value`. Echoes whatever the client sent. |
| B5 | `tools` always `[]` | Echoes the client's tools array in the response. |
| B7 | `temperature`/`top_p` wrong | Already defaults to `1.0` via `unwrap_or(1.0)`. Was a false positive — no fix needed. |
| Endpoint | Protocol | Primary Clients | Spec Reference |
| --------------------------- | --------------------------- | ----------------------------------------------------- | ------------------------------------------------------------------------------------------------------------ |
| `POST /v1/responses` | OpenAI Responses API | Claude Code, Antigravity-native clients | [platform.openai.com/docs/api-reference/responses](https://platform.openai.com/docs/api-reference/responses) |
| `POST /v1/chat/completions` | OpenAI Chat Completions API | OpenCode, Vercel AI SDK, any OpenAI-compatible client | [platform.openai.com/docs/api-reference/chat](https://platform.openai.com/docs/api-reference/chat/create) |
| `POST /v1/gemini` | Custom Gemini-native API | Direct Gemini-format consumers | [ai.google.dev/api](https://ai.google.dev/api) (loosely based) |
### Acceptable / Won't Fix
All three endpoints share the same backend pipeline:
```
Client Request → Proxy Endpoint → LS (Language Server) → Google API
MITM Proxy (captures real usage + injects generation params + tool calls)
```
| # | Bug | Status |
| --- | ----------------------------------------- | ----------------------------------------------------------------------------------------------------------- |
| B6 | `Usage::estimate` fake tokens as fallback | Only triggers on timeout/error paths. Heuristic `len/4` is reasonable for timeouts where output tokens = 0. |
---
## Feature Parity Matrix
## TODO — New Features
### Core Features
### Trivial (all done ✅)
| Feature | Responses | Completions | Gemini |
| -------------------- | :-------: | :---------: | :----: |
| Sync mode | ✅ | ✅ | ✅ |
| Streaming mode (SSE) | ✅ | ✅ | ✅ |
| Model selection | ✅ | ✅ | ✅ |
| Model validation | ✅ | ✅ | ✅ |
| Auth check (OAuth) | ✅ | ✅ | ✅ |
| Timeout control | ✅ | ✅ | ✅ |
All trivial response shape fixes have been implemented.
### Generation Parameters (MITM-injected)
### Medium (schema injection via MITM) — all done ✅
| Feature | Responses | Completions | Gemini |
| ------------------- | :-------: | :---------: | :----: |
| `temperature` | ✅ | ✅ | ✅ |
| `top_p` / `topP` | ✅ | ✅ | ✅ |
| `top_k` / `topK` | ❌ | ❌ | ✅ |
| `max_output_tokens` | ✅ | ✅ | ✅ |
| `stop_sequences` | ❌ | ❌ | ✅ |
| `frequency_penalty` | ❌ | ✅ | ❌ |
| `presence_penalty` | ❌ | ✅ | ❌ |
All structured output features have been implemented.
> **Note:** All generation parameters are forwarded to Google's API via MITM injection into `request.generationConfig`. They override the LS defaults.
### Hard (new features)
### Thinking / Reasoning
| # | Gap | API | Notes |
| --- | ------------------------- | ---- | ---------------------------------------------------------- |
| 7 | **`parallel_tool_calls`** | Both | Accept param, echo in response. Can't enforce server-side. |
| Feature | Responses | Completions | Gemini |
| ---------------------------------- | :-------------------------------: | :-------------------------------: | :---------------------: |
| Thinking — LS path (streaming) | ✅ `reasoning_summary_text.delta` | ✅ `reasoning_content` delta | ✅ `thought: true` part |
| Thinking — LS path (sync) | ✅ `reasoning` output item | ✅ `reasoning_content` in message | ✅ `thought: true` part |
| Thinking — Bypass path (streaming) | ✅ | ✅ | ✅ |
| Thinking — Bypass path (sync) | ✅ | ✅ | ✅ |
| Thinking signature (multi-turn) | ✅ `thinking_signature` field | ❌ Not applicable | ❌ Not applicable |
### Stretch (research needed)
### Tool Calls
| Feature | Responses | Completions | Gemini |
| ---------------------------- | :-----------------------------: | :------------------------: | :-------------------------------------: |
| Tool definitions input | ✅ OpenAI format → Gemini | ✅ OpenAI format → Gemini | ✅ Native Gemini format |
| Tool choice control | ✅ `tool_choice` | ✅ `tool_choice` | ✅ `tool_config` |
| Tool call output (streaming) | ✅ `function_call` items | ✅ `tool_calls` in delta | ✅ `functionCall` parts |
| Tool call output (sync) | ✅ `function_call` items | ✅ `tool_calls` in message | ✅ `functionCall` parts |
| Tool result input | ✅ `function_call_output` items | ✅ `tool` role messages | ✅ `functionResponse` in `tool_results` |
| MITM bypass (custom tools) | ✅ | ✅ | ✅ |
| Stale state protection | ✅ | ✅ | ✅ |
### Session Management
| Feature | Responses | Completions | Gemini |
| ------------------------------------ | :---------------------: | :--------------: | :---------------------: |
| Session/conversation reuse | ✅ `conversation` field | ❌ Not supported | ✅ `conversation` field |
| Session listing (`GET /v1/sessions`) | ✅ Shared | ✅ Shared | ✅ Shared |
| Session deletion | ✅ Shared | ✅ Shared | ✅ Shared |
### Usage / Token Tracking
| Feature | Responses | Completions | Gemini |
| -------------------------------- | :---------------------------: | :-------------------------------: | :--------------------------: |
| Usage in sync response | ✅ MITM real tokens | ✅ MITM real tokens | ✅ `usageMetadata` |
| Usage in streaming (final chunk) | ❌ Not emitted | ✅ `stream_options.include_usage` | ❌ Not emitted |
| `reasoning_tokens` in usage | ✅ In `output_tokens_details` | ✅ In `completion_tokens_details` | ✅ `thoughtsTokenCount` |
| Cache tokens | ✅ `cached_tokens` | ✅ `cached_tokens` | ✅ `cachedContentTokenCount` |
| # | Gap | API | Notes |
| --- | -------------------------- | ---- | ---------------------------------------------------------------------------------------------------------------------------- |
| 12 | **Image/audio modalities** | Both | LS `sendMessage` is text-only. Need to reverse-engineer proto format for binary payloads. Gemini 3 supports vision natively. |
---
## Detailed Endpoint Analysis
## Won't Implement
### Responses API (`/v1/responses`)
**Spec:** [OpenAI Responses API](https://platform.openai.com/docs/api-reference/responses)
#### Request Fields
| Field | Spec | Status | Implementation Details |
| ---------------------------- | ------------- | :----: | -------------------------------------------------------------------------------------------------------------------------------- |
| `model` | Required | ✅ | Mapped to internal model enum via `lookup_model()` |
| `input` | Required | ✅ | String or array. Array supports `message` items and `function_call_output` items |
| `instructions` | Optional | ✅ | Prepended to user text as system instructions |
| `stream` | Optional | ✅ | SSE stream with `response.*` events |
| `tools` | Optional | ✅ | OpenAI function format → auto-converted to Gemini `functionDeclarations` via `openai_tools_to_gemini()` |
| `tool_choice` | Optional | ✅ | `"auto"`, `"required"`, `"none"`, or `{"type":"function","function":{"name":"X"}}` → converted to Gemini `functionCallingConfig` |
| `store` | Optional | ✅ | Accepted, echoed in response. Not actually persisted. |
| `temperature` | Optional | ✅ | **Forwarded** to Google via MITM `generationConfig` injection. |
| `top_p` | Optional | ✅ | **Forwarded** to Google via MITM. |
| `max_output_tokens` | Optional | ✅ | **Forwarded** to Google via MITM. |
| `previous_response_id` | Optional | ✅ | Accepted, echoed. Not used for chaining (use `conversation` instead). |
| `metadata` | Optional | ✅ | Accepted, echoed back in response. |
| `user` | Optional | ✅ | Accepted, echoed. |
| `conversation` | **Extension** | ✅ | Proxy-specific: session ID for multi-turn cascade reuse. |
| `timeout` | **Extension** | ✅ | Proxy-specific: request timeout in seconds (default 120). |
| `reasoning.effort` | Optional | ❌ | Could map to model variant selection (e.g., `"high"` → Opus, `"low"` → Flash). |
| `reasoning.generate_summary` | Optional | ❌ | Not implemented. Could control thinking output inclusion. |
| `truncation` | Optional | ❌ | Not applicable — LS manages context window. |
| `parallel_tool_calls` | Optional | ✅ | Hardcoded `true` in response. |
#### Response Object
| Field | Spec | Status | Notes |
| ---------------------- | ------------- | :----: | ---------------------------------------------------------------- |
| `id` | Required | ✅ | `resp_` + UUID |
| `object` | Required | ✅ | Always `"response"` |
| `created_at` | Required | ✅ | Unix timestamp |
| `status` | Required | ✅ | `"completed"` or `"incomplete"` |
| `completed_at` | Required | ✅ | Unix timestamp or null |
| `error` | Required | ✅ | null on success |
| `incomplete_details` | Required | ✅ | null |
| `instructions` | Required | ✅ | Echoed from request |
| `max_output_tokens` | Required | ✅ | Echoed or null |
| `model` | Required | ✅ | Model name string |
| `output` | Required | ✅ | Array of `reasoning` and/or `message` items |
| `parallel_tool_calls` | Required | ✅ | `true` |
| `previous_response_id` | Required | ✅ | Echoed or null |
| `reasoning` | Required | ✅ | `{effort: null, summary: null}` |
| `store` | Required | ✅ | Echoed |
| `temperature` | Required | ✅ | Echoed (default 1.0) |
| `text` | Required | ✅ | `{format: {type: "text"}}` |
| `tool_choice` | Required | ✅ | `"auto"` |
| `tools` | Required | ✅ | Echoed or `[]` |
| `top_p` | Required | ✅ | Echoed (default 1.0) |
| `truncation` | Required | ✅ | `"disabled"` |
| `usage` | Required | ✅ | MITM-intercepted real tokens when available, estimated otherwise |
| `user` | Required | ✅ | Echoed or null |
| `metadata` | Required | ✅ | Echoed or `{}` |
| `thinking_signature` | **Extension** | ✅ | Proxy-specific: opaque blob for multi-turn thinking chain |
#### Streaming Events
| Event | Spec | Status | Notes |
| ---------------------------------------- | --------- | :----: | ------------------------------ |
| `response.created` | Required | ✅ | Initial response shell |
| `response.in_progress` | Required | ✅ | |
| `response.output_item.added` | Required | ✅ | For reasoning + message items |
| `response.content_part.added` | Required | ✅ | |
| `response.output_text.delta` | Required | ✅ | Progressive text deltas |
| `response.output_text.done` | Required | ✅ | |
| `response.content_part.done` | Required | ✅ | |
| `response.output_item.done` | Required | ✅ | |
| `response.completed` | Required | ✅ | Final event with full response |
| `response.reasoning_summary_text.delta` | Required | ✅ | Progressive thinking deltas |
| `response.reasoning_summary_text.done` | Required | ✅ | |
| `response.function_call_arguments.delta` | For tools | ✅ | Tool call argument streaming |
| `response.function_call_arguments.done` | For tools | ✅ | |
---
### Chat Completions API (`/v1/chat/completions`)
**Spec:** [OpenAI Chat Completions API](https://platform.openai.com/docs/api-reference/chat/create)
#### Request Fields
| Field | Spec | Status | Implementation Details |
| ------------------------- | ------------- | :----: | -------------------------------------------------------------------- |
| `model` | Required | ✅ | Mapped to internal model enum |
| `messages` | Required | ✅ | Supports `system`, `developer`, `user`, `assistant`, `tool` roles |
| `messages[].content` | Required | ✅ | String or array of `{type: "text", text: "..."}` objects |
| `messages[].tool_calls` | Optional | ✅ | For assistant messages with tool calls |
| `messages[].tool_call_id` | Optional | ✅ | For tool result messages |
| `stream` | Optional | ✅ | SSE with `chat.completion.chunk` events |
| `stream_options` | Optional | ✅ | `include_usage: true` emits final usage chunk before `[DONE]` |
| `tools` | Optional | ✅ | OpenAI function format → auto-converted to Gemini |
| `tool_choice` | Optional | ✅ | `"auto"`, `"none"`, `"required"`, or specific function |
| `timeout` | **Extension** | ✅ | Proxy-specific (default 120s) |
| `temperature` | Optional | ✅ | **Forwarded** to Google via MITM `generationConfig.temperature` |
| `top_p` | Optional | ✅ | **Forwarded** to Google via MITM `generationConfig.topP` |
| `max_tokens` | Optional | ✅ | **Forwarded** to Google via MITM `generationConfig.maxOutputTokens` |
| `max_completion_tokens` | Optional | ✅ | **Forwarded** (same as `max_tokens`, newer OpenAI param) |
| `frequency_penalty` | Optional | ✅ | **Forwarded** to Google via MITM `generationConfig.frequencyPenalty` |
| `presence_penalty` | Optional | ✅ | **Forwarded** to Google via MITM `generationConfig.presencePenalty` |
| `user` | Optional | ✅ | Accepted, not used |
| `n` | Optional | ❌ | N/A — single generation only |
| `logprobs` | Optional | ❌ | N/A |
| `top_logprobs` | Optional | ❌ | N/A |
| `logit_bias` | Optional | ❌ | N/A |
| `response_format` | Optional | ❌ | Could be useful for JSON mode |
| `seed` | Optional | ❌ | N/A |
| `stop` | Optional | ❌ | Could be forwarded as `stopSequences` |
#### Sync Response Object
| Field | Spec | Status | Notes |
| ------------------------------------------------------------ | ----------- | :----: | -------------------------------------------- |
| `id` | Required | ✅ | `chatcmpl-` + UUID |
| `object` | Required | ✅ | `"chat.completion"` |
| `created` | Required | ✅ | Unix timestamp |
| `model` | Required | ✅ | Model name |
| `choices[0].index` | Required | ✅ | `0` |
| `choices[0].message.role` | Required | ✅ | `"assistant"` |
| `choices[0].message.content` | Required | ✅ | Response text |
| `choices[0].message.reasoning_content` | Extension | ✅ | Thinking text (when model produces thinking) |
| `choices[0].message.tool_calls` | Conditional | ✅ | When model returns tool calls |
| `choices[0].message.refusal` | Optional | ❌ | Not implemented |
| `choices[0].message.annotations` | Optional | ❌ | Not implemented |
| `choices[0].logprobs` | Optional | ❌ | Not implemented |
| `choices[0].finish_reason` | Required | ✅ | `"stop"` or `"tool_calls"` |
| `usage.prompt_tokens` | Required | ✅ | MITM real or estimated |
| `usage.completion_tokens` | Required | ✅ | MITM real or estimated |
| `usage.total_tokens` | Required | ✅ | Sum |
| `usage.prompt_tokens_details.cached_tokens` | Optional | ✅ | MITM cache read tokens |
| `usage.completion_tokens_details.reasoning_tokens` | Optional | ✅ | MITM thinking token count |
| `usage.completion_tokens_details.accepted_prediction_tokens` | Optional | ❌ | N/A |
| `usage.completion_tokens_details.rejected_prediction_tokens` | Optional | ❌ | N/A |
| `system_fingerprint` | Deprecated | ❌ | Cosmetic, not needed |
| `service_tier` | Optional | ❌ | Cosmetic, not needed |
#### Streaming Chunk Object
| Field | Spec | Status | Notes |
| ------------------------------------ | --------------- | :----: | ----------------------------------------------------- |
| `id` | Required | ✅ | Same across all chunks |
| `object` | Required | ✅ | `"chat.completion.chunk"` |
| `created` | Required | ✅ | Same across all chunks |
| `model` | Required | ✅ | |
| `choices[0].index` | Required | ✅ | `0` |
| `choices[0].delta.role` | First chunk | ✅ | `"assistant"` in first chunk |
| `choices[0].delta.content` | Text chunks | ✅ | Progressive text deltas |
| `choices[0].delta.reasoning_content` | Thinking chunks | ✅ | Progressive thinking deltas |
| `choices[0].delta.tool_calls` | Tool chunks | ✅ | Tool call data |
| `choices[0].delta` | Final chunk | ✅ | Empty `{}` |
| `choices[0].finish_reason` | Final chunk | ✅ | `"stop"` or `"tool_calls"` |
| `choices[0].logprobs` | Optional | ❌ | Not implemented |
| `usage` (final chunk) | Optional | ✅ | Emitted when `stream_options.include_usage` is `true` |
| `data: [DONE]` | Required | ✅ | Stream termination signal |
---
### Gemini API (`/v1/gemini`)
**Spec:** Custom endpoint loosely based on [Gemini REST API](https://ai.google.dev/api/generate-content)
> **Note:** This is NOT a 1:1 Gemini API replica. It's a simplified proxy-native endpoint that uses Gemini's `functionDeclarations` / `functionCall` / `functionResponse` format directly, avoiding OpenAI ↔ Gemini format conversion overhead.
#### Request Fields
| Field | Spec | Status | Implementation Details |
| --------------------------------------- | -------- | :----: | --------------------------------------------------------------- |
| `model` | Required | ✅ | Mapped to internal model enum |
| `input` | Required | ✅ | String only (no array/multipart) |
| `tools` | Optional | ✅ | Native Gemini `[{functionDeclarations: [...]}]` format |
| `tool_config` | Optional | ✅ | Native Gemini `{functionCallingConfig: {mode: "AUTO"}}` |
| `tool_results` | Optional | ✅ | Array of `{functionResponse: {name, response}}` |
| `conversation` | Optional | ✅ | Session ID for cascade reuse |
| `stream` | Optional | ✅ | SSE streaming |
| `timeout` | Optional | ✅ | Default 120s |
| `temperature` | Optional | ✅ | **Forwarded** to Google via MITM `generationConfig.temperature` |
| `top_p` / `topP` | Optional | ✅ | **Forwarded** to Google via MITM `generationConfig.topP` |
| `top_k` / `topK` | Optional | ✅ | **Forwarded** to Google via MITM `generationConfig.topK` |
| `max_output_tokens` / `maxOutputTokens` | Optional | ✅ | **Forwarded** via MITM `generationConfig.maxOutputTokens` |
| `stop_sequences` / `stopSequences` | Optional | ✅ | **Forwarded** via MITM `generationConfig.stopSequences` |
#### Sync Response Object
| Field | Spec | Status | Notes |
| -------------------------------------------- | --------- | :----: | -------------------------------- |
| `candidates[0].content.parts` | Required | ✅ | Array of text/functionCall parts |
| `candidates[0].content.parts[].text` | Text | ✅ | Response text |
| `candidates[0].content.parts[].thought` | Extension | ✅ | `true` for thinking parts |
| `candidates[0].content.parts[].functionCall` | Tool call | ✅ | `{name, args}` |
| `candidates[0].content.role` | Required | ✅ | `"model"` |
| `candidates[0].finishReason` | Required | ✅ | `"STOP"` |
| `modelVersion` | Required | ✅ | Model name string |
| `usageMetadata` | Optional | ✅ | MITM-intercepted token counts |
`usageMetadata` fields:
| Field | Status | Notes |
| ------------------------- | :----: | ------------------------- |
| `promptTokenCount` | ✅ | Input tokens |
| `candidatesTokenCount` | ✅ | Output tokens |
| `totalTokenCount` | ✅ | Input + output |
| `thoughtsTokenCount` | ✅ | Thinking/reasoning tokens |
| `cachedContentTokenCount` | ✅ | Cache read tokens |
#### Streaming Format
Each SSE `data:` chunk is a complete Gemini-format JSON object with progressive `candidates[0].content.parts`:
```
data: {"candidates":[{"content":{"parts":[{"text":"thinking...","thought":true}],"role":"model"}}],"modelVersion":"opus-4.6"}
data: {"candidates":[{"content":{"parts":[{"text":"Hello!"}],"role":"model"}}],"modelVersion":"opus-4.6"}
data: {"candidates":[{"content":{"parts":[{"text":""}],"role":"model"},"finishReason":"STOP"}],"modelVersion":"opus-4.6"}
data: [DONE]
```
---
## Priority Gaps
### 🔴 High Priority — RESOLVED ✅
All high-priority gaps have been addressed:
1. ~~**Completions: `stream_options.include_usage`**~~ → ✅ Implemented
2. ~~**Completions: `completion_tokens_details.reasoning_tokens`**~~ → ✅ Implemented
3. ~~**Completions: Accept `temperature`, `top_p`, `max_tokens`**~~ → ✅ Forwarded via MITM
4. ~~**Gemini: `usageMetadata`**~~ → ✅ Implemented
### 🟡 Medium Priority
5. **Responses: `reasoning.effort`**
- **What:** Map reasoning effort levels (`"high"`, `"medium"`, `"low"`) to model variant selection
- **Why:** Could automatically select Opus vs Flash based on reasoning needs
- **Effort:** Medium — needs model selection logic changes
6. **Completions: Session/conversation support**
- **What:** Add session reuse similar to Responses and Gemini endpoints
- **Why:** Would allow multi-turn conversations via the completions API
- **Effort:** Medium — need a way to pass session ID (maybe via `user` field or custom header)
7. **Completions: `stop` sequences**
- **What:** Forward `stop` to Google as `stopSequences` in `generationConfig`
- **Why:** Some clients use stop sequences to control generation
- **Effort:** Trivial — just add to `CompletionRequest` and `GenerationParams`
8. **Completions: `response_format` (JSON mode)**
- **What:** Forward `response_format: {"type": "json_object"}` to Google's `responseMimeType`
- **Why:** Useful for structured output
- **Effort:** Low — inject `responseMimeType: "application/json"` in generationConfig
### 🟢 Low Priority
Cosmetic or not applicable to our architecture:
9. **`system_fingerprint`** — OpenAI-specific field, meaningless for our proxy
10. **`service_tier`** — OpenAI billing concept, not applicable
11. **`n` > 1** — Multiple completions per request; our backend only generates one
12. **`logprobs`** — Would require token-level access we don't have
13. **`seed`** — Deterministic sampling not controllable through our proxy
---
## Architecture Notes
### Generation Parameter Injection
Client-specified sampling parameters are forwarded to Google's API via the MITM request modification pipeline:
```
Client sends temperature=0.5 → API handler stores in MitmStore.generation_params
LS sends request to Google API
MITM intercepts request
modify_request() reads generation_params
Injects into request.generationConfig:
temperature, topP, topK, maxOutputTokens,
stopSequences, frequencyPenalty, presencePenalty
Forwards modified request to Google
```
This approach overrides whatever defaults the LS sets, giving clients direct control over sampling parameters.
### Dual Path Architecture
All three endpoints share a dual-path architecture:
```
┌─────────────────┐
│ Has custom │
Request ────────────► │ tools? │
└────────┬────────┘
┌──── Yes ──┴── No ────┐
│ │
┌─────▼─────┐ ┌─────▼─────┐
│ MITM │ │ LS Steps │
│ Bypass │ │ Polling │
│ Path │ │ Path │
└─────┬─────┘ └─────┬─────┘
│ │
┌─────▼─────┐ ┌─────▼─────┐
│ Poll │ │ Poll │
│ MitmStore │ │ get_steps │
│ directly │ │ from LS │
└─────┬─────┘ └─────┬─────┘
│ │
└──────────┬────────────┘
┌─────▼─────┐
│ Response │
│ to client │
└───────────┘
```
- **Bypass Path:** When custom tools are present, the handler polls `MitmStore` directly for response text, thinking text, and function calls. The MITM proxy captures these from the Google API response before the LS processes them.
- **LS Path:** When no custom tools are present, the handler polls the LS's `get_steps` API for progressive response data (text, thinking, status).
### Stale State Protection
All bypass paths include protection against stale `response_complete` flags from previous requests:
```rust
if complete && text.is_empty() && thinking.is_none() {
warn!("stale response_complete detected — clearing");
state.mitm_store.clear_response_async().await;
continue; // or retry
}
```
This handles the race condition where a previous request's MITM handler calls `mark_response_complete()` after the new request has already called `clear_response_async()`.
### Tool Format Conversion
```
OpenAI tools ──► openai_tools_to_gemini() ──► Gemini functionDeclarations
MitmStore.set_tools()
MITM proxy injects into
outgoing LS request
```
The Gemini endpoint skips this conversion entirely — tools are stored in native Gemini format.
| # | Gap | Reason |
| --- | ------------------------------- | ------------------------------------------------------------------------ |
| 9 | `prediction` (Predicted Output) | Inference-level speculative decoding optimization. No Gemini equivalent. |
| 10 | `logprobs` / `top_logprobs` | Gemini never exposes token-level log probabilities. |

View File

@@ -15,45 +15,77 @@ use super::types::*;
use super::util::{err_response, now_unix};
use super::AppState;
/// Extract a conversation/session ID from a flexible JSON value.
/// Accepts a plain string or an object with an "id" field.
fn extract_conversation_id(conv: &Option<serde_json::Value>) -> Option<String> {
match conv {
Some(serde_json::Value::String(s)) => Some(s.clone()),
Some(obj) => obj["id"].as_str().map(|s| s.to_string()),
None => None,
}
}
/// System fingerprint for completions responses (derived from crate version at compile time).
fn system_fingerprint() -> String {
format!("fp_{}", env!("CARGO_PKG_VERSION").replace('.', ""))
}
/// Build a streaming chunk JSON with all required OpenAI fields.
/// Includes system_fingerprint, service_tier, and logprobs:null in choices.
fn chunk_json(
id: &str, model: &str,
choices: serde_json::Value,
usage: Option<serde_json::Value>,
) -> String {
let mut obj = serde_json::json!({
"id": id,
"object": "chat.completion.chunk",
"created": now_unix(),
"model": model,
"system_fingerprint": system_fingerprint(),
"service_tier": "default",
"choices": choices,
});
if let Some(u) = usage {
obj["usage"] = u;
}
serde_json::to_string(&obj).unwrap_or_default()
}
/// Build a single choice for a streaming chunk (delta + finish_reason + logprobs).
fn chunk_choice(index: u32, delta: serde_json::Value, finish_reason: Option<&str>) -> serde_json::Value {
serde_json::json!({
"index": index,
"delta": delta,
"logprobs": serde_json::Value::Null,
"finish_reason": finish_reason,
})
}
// ─── Finish reason mapping ───────────────────────────────────────────────────
/// Map Google's finishReason → OpenAI's finish_reason.
/// Google: STOP, MAX_TOKENS, SAFETY, RECITATION, OTHER, BLOCKLIST, PROHIBITED_CONTENT
/// OpenAI: stop, length, content_filter, tool_calls (handled separately)
fn google_to_openai_finish_reason(stop_reason: Option<&str>) -> &'static str {
match stop_reason {
Some("MAX_TOKENS") => "length",
Some("SAFETY") | Some("RECITATION") | Some("BLOCKLIST") | Some("PROHIBITED_CONTENT") => "content_filter",
_ => "stop",
}
}
// ─── Input extraction ────────────────────────────────────────────────────────
/// Extract user text from Chat Completions messages array.
///
/// When tool results are present, builds the full conversation including
/// tool call results so the model can continue after tool use.
/// Builds the full conversation context including all messages (system, user,
/// assistant, tool) so the model has complete history — matching how OpenAI
/// sends the entire messages array to the model.
fn extract_chat_input(messages: &[CompletionMessage]) -> String {
let has_tool_results = messages.iter().any(|m| m.role == "tool");
if has_tool_results {
// Build full conversation context including tool results
return build_conversation_with_tools(messages);
}
// Simple path: no tools, just extract system + last user message
let mut system_parts = Vec::new();
let mut user_parts = Vec::new();
for msg in messages {
let text = extract_message_text(&msg.content);
if text.is_empty() {
continue;
}
match msg.role.as_str() {
"system" | "developer" => system_parts.push(text),
"user" => user_parts.push(text),
_ => {}
}
}
let mut result = String::new();
if !system_parts.is_empty() {
result.push_str(&system_parts.join("\n"));
result.push_str("\n\n");
}
if let Some(last) = user_parts.last() {
result.push_str(last);
}
result.trim().to_string()
// Always build the full conversation — we used to only take the last user
// message which broke multi-turn conversations via the messages array.
build_conversation_with_tools(messages)
}
/// Extract text content from a message's content field (string or array).
@@ -179,18 +211,36 @@ pub(crate) async fn handle_completions(
// Store generation parameters for MITM injection
{
use crate::mitm::store::GenerationParams;
let (response_mime_type, response_schema) = match body.response_format.as_ref() {
Some(rf) => match rf.format_type.as_str() {
"json_object" | "json" => (Some("application/json".to_string()), None),
"json_schema" => {
let schema = rf.json_schema.as_ref().and_then(|js| js.schema.clone());
(Some("application/json".to_string()), schema)
}
_ => (None, None),
},
None => (None, None),
};
let gp = GenerationParams {
temperature: body.temperature,
top_p: body.top_p,
top_k: None, // OpenAI doesn't have top_k
max_output_tokens: body.max_tokens.or(body.max_completion_tokens),
stop_sequences: None, // TODO: body.stop
stop_sequences: body.stop.clone().map(|s| s.into_vec()),
frequency_penalty: body.frequency_penalty,
presence_penalty: body.presence_penalty,
reasoning_effort: body.reasoning_effort.clone(),
response_mime_type,
response_schema,
google_search: body.web_search,
};
// Only store if at least one param is set
if gp.temperature.is_some() || gp.top_p.is_some() || gp.max_output_tokens.is_some()
|| gp.frequency_penalty.is_some() || gp.presence_penalty.is_some()
|| gp.reasoning_effort.is_some() || gp.stop_sequences.is_some()
|| gp.response_mime_type.is_some() || gp.response_schema.is_some()
|| gp.google_search
{
state.mitm_store.set_generation_params(gp).await;
} else {
@@ -216,8 +266,28 @@ pub(crate) async fn handle_completions(
);
}
// Fresh cascade per request
let cascade_id = match state.backend.create_cascade().await {
let n = (body.n.max(1)).min(5); // Cap at 5 to prevent abuse
if n > 1 && body.stream {
warn!("n={n} requested with streaming — streaming only supports n=1, ignoring n");
}
// Session/conversation: reuse cascade if conversation ID provided
let session_id_str = extract_conversation_id(&body.conversation);
// Helper to create a cascade (reuses session or creates fresh)
let create_cascade = |state: Arc<AppState>, session_id: Option<String>| async move {
if let Some(ref sid) = session_id {
state
.sessions
.get_or_create(Some(sid), || state.backend.create_cascade())
.await
.map(|sr| sr.cascade_id)
} else {
state.backend.create_cascade().await
}
};
let cascade_id = match create_cascade(Arc::clone(&state), session_id_str.clone()).await {
Ok(cid) => cid,
Err(e) => {
return err_response(
@@ -228,7 +298,7 @@ pub(crate) async fn handle_completions(
}
};
// Send message
// Send message on primary cascade
state.mitm_store.set_active_cascade(&cascade_id).await;
match state
.backend
@@ -275,7 +345,7 @@ pub(crate) async fn handle_completions(
include_usage,
)
.await
} else {
} else if n <= 1 {
chat_completions_sync(
state,
completion_id,
@@ -284,6 +354,108 @@ pub(crate) async fn handle_completions(
body.timeout,
)
.await
} else {
// n > 1: fire additional (n-1) parallel cascades
let mut extra_cascade_ids = Vec::with_capacity((n - 1) as usize);
for _ in 1..n {
match state.backend.create_cascade().await {
Ok(cid) => {
// Send the same message on each extra cascade
match state.backend.send_message(&cid, &user_text, model.model_enum).await {
Ok((200, _)) => {
let bg = Arc::clone(&state.backend);
let cid2 = cid.clone();
tokio::spawn(async move { let _ = bg.update_annotations(&cid2).await; });
extra_cascade_ids.push(cid);
}
_ => {} // Skip failed cascades
}
}
Err(_) => {} // Skip failed cascade creation
}
}
// Poll all cascades in parallel
let mut handles = Vec::with_capacity(n as usize);
let all_cascade_ids: Vec<String> = std::iter::once(cascade_id.clone())
.chain(extra_cascade_ids)
.collect();
for cid in &all_cascade_ids {
let st = Arc::clone(&state);
let cid = cid.clone();
let timeout = body.timeout;
handles.push(tokio::spawn(async move {
let result = poll_for_response(&st, &cid, timeout).await;
let mitm = match st.mitm_store.take_usage(&cid).await {
Some(u) => Some(u),
None => st.mitm_store.take_usage("_latest").await,
};
(result, mitm)
}));
}
let mut choices = Vec::with_capacity(n as usize);
let mut total_prompt = 0u64;
let mut total_completion = 0u64;
let mut total_cached = 0u64;
let mut total_thinking = 0u64;
for (i, handle) in handles.into_iter().enumerate() {
if let Ok((result, mitm)) = handle.await {
let finish_reason = google_to_openai_finish_reason(
mitm.as_ref().and_then(|u| u.stop_reason.as_deref()),
);
let (pt, ct, cached, thinking) = if let Some(ref mu) = mitm {
(mu.input_tokens, mu.output_tokens, mu.cache_read_input_tokens, mu.thinking_output_tokens)
} else if let Some(u) = &result.usage {
(u.input_tokens, u.output_tokens, 0, 0)
} else {
(0, 0, 0, 0)
};
total_prompt += pt;
total_completion += ct;
total_cached += cached;
total_thinking += thinking;
let mut message = serde_json::json!({
"role": "assistant",
"content": result.text,
});
if let Some(ref thinking_text) = result.thinking {
message["reasoning_content"] = serde_json::json!(thinking_text);
}
choices.push(serde_json::json!({
"index": i,
"message": message,
"logprobs": serde_json::Value::Null,
"finish_reason": finish_reason,
}));
}
}
Json(serde_json::json!({
"id": completion_id,
"object": "chat.completion",
"created": now_unix(),
"model": model_name,
"system_fingerprint": system_fingerprint(),
"service_tier": "default",
"choices": choices,
"usage": {
"prompt_tokens": total_prompt,
"completion_tokens": total_completion,
"total_tokens": total_prompt + total_completion,
"prompt_tokens_details": {
"cached_tokens": total_cached,
},
"completion_tokens_details": {
"reasoning_tokens": total_thinking,
},
},
}))
.into_response()
}
}
@@ -307,21 +479,26 @@ async fn chat_completions_stream(
state.mitm_store.clear_response_async().await;
// Initial role chunk
yield Ok::<_, std::convert::Infallible>(Event::default().data(serde_json::to_string(&serde_json::json!({
"id": completion_id,
"object": "chat.completion.chunk",
"created": now_unix(),
"model": model_name,
"choices": [{
"index": 0,
"delta": {"role": "assistant", "content": ""},
"finish_reason": serde_json::Value::Null,
}],
})).unwrap_or_default()));
yield Ok::<_, std::convert::Infallible>(Event::default().data(chunk_json(
&completion_id, &model_name,
serde_json::json!([chunk_choice(0, serde_json::json!({"role": "assistant", "content": ""}), None)]),
None,
)));
let mut keepalive_counter: u64 = 0;
let mut last_thinking_len: usize = 0;
// Helper: build usage JSON from MITM tokens
let build_usage = |pt: u64, ct: u64, crt: u64, tt: u64| -> serde_json::Value {
serde_json::json!({
"prompt_tokens": pt,
"completion_tokens": ct,
"total_tokens": pt + ct,
"prompt_tokens_details": { "cached_tokens": crt },
"completion_tokens_details": { "reasoning_tokens": tt },
})
};
while start.elapsed().as_secs() < timeout {
// ── Check for MITM-captured function calls FIRST ──
// This runs independently of LS steps — the MITM captures tool calls
@@ -346,49 +523,28 @@ async fn chat_completions_stream(
},
}));
}
yield Ok(Event::default().data(serde_json::to_string(&serde_json::json!({
"id": completion_id,
"object": "chat.completion.chunk",
"created": now_unix(),
"model": model_name,
"choices": [{
"index": 0,
"delta": {"tool_calls": tool_calls},
"finish_reason": serde_json::Value::Null,
}],
})).unwrap_or_default()));
yield Ok(Event::default().data(chunk_json(
&completion_id, &model_name,
serde_json::json!([chunk_choice(0, serde_json::json!({"tool_calls": tool_calls}), None)]),
None,
)));
yield Ok(Event::default().data(serde_json::to_string(&serde_json::json!({
"id": completion_id,
"object": "chat.completion.chunk",
"created": now_unix(),
"model": model_name,
"choices": [{
"index": 0,
"delta": {},
"finish_reason": "tool_calls",
}],
})).unwrap_or_default()));
yield Ok(Event::default().data(chunk_json(
&completion_id, &model_name,
serde_json::json!([chunk_choice(0, serde_json::json!({}), Some("tool_calls"))]),
None,
)));
if include_usage {
let mitm = state.mitm_store.take_usage(&cascade_id).await
.or(state.mitm_store.take_usage("_latest").await);
let (pt, ct, crt, tt) = if let Some(ref u) = mitm {
(u.input_tokens, u.output_tokens, u.cache_read_input_tokens, u.thinking_output_tokens)
} else { (0, 0, 0, 0) };
yield Ok(Event::default().data(serde_json::to_string(&serde_json::json!({
"id": completion_id,
"object": "chat.completion.chunk",
"created": now_unix(),
"model": model_name,
"choices": [],
"usage": {
"prompt_tokens": pt,
"completion_tokens": ct,
"total_tokens": pt + ct,
"prompt_tokens_details": { "cached_tokens": crt },
"completion_tokens_details": { "reasoning_tokens": tt },
},
})).unwrap_or_default()));
yield Ok(Event::default().data(chunk_json(
&completion_id, &model_name,
serde_json::json!([]),
Some(build_usage(pt, ct, crt, tt)),
)));
}
yield Ok(Event::default().data("[DONE]"));
return;
@@ -413,17 +569,11 @@ async fn chat_completions_stream(
let delta = &tc[last_thinking_len..];
last_thinking_len = tc.len();
yield Ok(Event::default().data(serde_json::to_string(&serde_json::json!({
"id": completion_id,
"object": "chat.completion.chunk",
"created": now_unix(),
"model": model_name,
"choices": [{
"index": 0,
"delta": {"reasoning_content": delta},
"finish_reason": serde_json::Value::Null,
}],
})).unwrap_or_default()));
yield Ok(Event::default().data(chunk_json(
&completion_id, &model_name,
serde_json::json!([chunk_choice(0, serde_json::json!({"reasoning_content": delta}), None)]),
None,
)));
}
}
@@ -436,17 +586,11 @@ async fn chat_completions_stream(
};
if !delta.is_empty() {
yield Ok(Event::default().data(serde_json::to_string(&serde_json::json!({
"id": completion_id,
"object": "chat.completion.chunk",
"created": now_unix(),
"model": model_name,
"choices": [{
"index": 0,
"delta": {"content": delta},
"finish_reason": serde_json::Value::Null,
}],
})).unwrap_or_default()));
yield Ok(Event::default().data(chunk_json(
&completion_id, &model_name,
serde_json::json!([chunk_choice(0, serde_json::json!({"content": delta}), None)]),
None,
)));
last_text = text;
}
}
@@ -454,37 +598,24 @@ async fn chat_completions_stream(
// Check if MITM response is complete
if state.mitm_store.is_response_complete() && !last_text.is_empty() {
debug!("Completions: MITM response complete (bypass), text length={}", last_text.len());
yield Ok(Event::default().data(serde_json::to_string(&serde_json::json!({
"id": completion_id,
"object": "chat.completion.chunk",
"created": now_unix(),
"model": model_name,
"choices": [{
"index": 0,
"delta": {},
"finish_reason": "stop",
}],
})).unwrap_or_default()));
// Take usage FIRST so we can read stop_reason for finish_reason
let mitm = state.mitm_store.take_usage(&cascade_id).await
.or(state.mitm_store.take_usage("_latest").await);
let fr = google_to_openai_finish_reason(mitm.as_ref().and_then(|u| u.stop_reason.as_deref()));
yield Ok(Event::default().data(chunk_json(
&completion_id, &model_name,
serde_json::json!([chunk_choice(0, serde_json::json!({}), Some(fr))]),
None,
)));
if include_usage {
let mitm = state.mitm_store.take_usage(&cascade_id).await
.or(state.mitm_store.take_usage("_latest").await);
let (pt, ct, crt, tt) = if let Some(ref u) = mitm {
(u.input_tokens, u.output_tokens, u.cache_read_input_tokens, u.thinking_output_tokens)
} else { (0, 0, 0, 0) };
yield Ok(Event::default().data(serde_json::to_string(&serde_json::json!({
"id": completion_id,
"object": "chat.completion.chunk",
"created": now_unix(),
"model": model_name,
"choices": [],
"usage": {
"prompt_tokens": pt,
"completion_tokens": ct,
"total_tokens": pt + ct,
"prompt_tokens_details": { "cached_tokens": crt },
"completion_tokens_details": { "reasoning_tokens": tt },
},
})).unwrap_or_default()));
yield Ok(Event::default().data(chunk_json(
&completion_id, &model_name,
serde_json::json!([]),
Some(build_usage(pt, ct, crt, tt)),
)));
}
yield Ok(Event::default().data("[DONE]"));
return;
@@ -514,48 +645,27 @@ async fn chat_completions_stream(
},
}));
}
yield Ok(Event::default().data(serde_json::to_string(&serde_json::json!({
"id": completion_id,
"object": "chat.completion.chunk",
"created": now_unix(),
"model": model_name,
"choices": [{
"index": 0,
"delta": {"tool_calls": tool_calls},
"finish_reason": serde_json::Value::Null,
}],
})).unwrap_or_default()));
yield Ok(Event::default().data(serde_json::to_string(&serde_json::json!({
"id": completion_id,
"object": "chat.completion.chunk",
"created": now_unix(),
"model": model_name,
"choices": [{
"index": 0,
"delta": {},
"finish_reason": "tool_calls",
}],
})).unwrap_or_default()));
yield Ok(Event::default().data(chunk_json(
&completion_id, &model_name,
serde_json::json!([chunk_choice(0, serde_json::json!({"tool_calls": tool_calls}), None)]),
None,
)));
yield Ok(Event::default().data(chunk_json(
&completion_id, &model_name,
serde_json::json!([chunk_choice(0, serde_json::json!({}), Some("tool_calls"))]),
None,
)));
if include_usage {
let mitm = state.mitm_store.take_usage(&cascade_id).await
.or(state.mitm_store.take_usage("_latest").await);
let (pt, ct, crt, tt) = if let Some(ref u) = mitm {
(u.input_tokens, u.output_tokens, u.cache_read_input_tokens, u.thinking_output_tokens)
} else { (0, 0, 0, 0) };
yield Ok(Event::default().data(serde_json::to_string(&serde_json::json!({
"id": completion_id,
"object": "chat.completion.chunk",
"created": now_unix(),
"model": model_name,
"choices": [],
"usage": {
"prompt_tokens": pt,
"completion_tokens": ct,
"total_tokens": pt + ct,
"prompt_tokens_details": { "cached_tokens": crt },
"completion_tokens_details": { "reasoning_tokens": tt },
},
})).unwrap_or_default()));
yield Ok(Event::default().data(chunk_json(
&completion_id, &model_name,
serde_json::json!([]),
Some(build_usage(pt, ct, crt, tt)),
)));
}
yield Ok(Event::default().data("[DONE]"));
return;
@@ -587,17 +697,11 @@ async fn chat_completions_stream(
let delta = &tc[last_thinking_len..];
last_thinking_len = tc.len();
yield Ok(Event::default().data(serde_json::to_string(&serde_json::json!({
"id": completion_id,
"object": "chat.completion.chunk",
"created": now_unix(),
"model": model_name,
"choices": [{
"index": 0,
"delta": {"reasoning_content": delta},
"finish_reason": serde_json::Value::Null,
}],
})).unwrap_or_default()));
yield Ok(Event::default().data(chunk_json(
&completion_id, &model_name,
serde_json::json!([chunk_choice(0, serde_json::json!({"reasoning_content": delta}), None)]),
None,
)));
}
}
@@ -611,17 +715,11 @@ async fn chat_completions_stream(
};
if !delta.is_empty() {
yield Ok(Event::default().data(serde_json::to_string(&serde_json::json!({
"id": completion_id,
"object": "chat.completion.chunk",
"created": now_unix(),
"model": model_name,
"choices": [{
"index": 0,
"delta": {"content": delta},
"finish_reason": serde_json::Value::Null,
}],
})).unwrap_or_default()));
yield Ok(Event::default().data(chunk_json(
&completion_id, &model_name,
serde_json::json!([chunk_choice(0, serde_json::json!({"content": delta}), None)]),
None,
)));
last_text = text.to_string();
}
}
@@ -629,37 +727,23 @@ async fn chat_completions_stream(
// Done check: need DONE status AND non-empty text
if is_response_done(steps) && !last_text.is_empty() {
debug!("Completions stream done, text length={}", last_text.len());
yield Ok(Event::default().data(serde_json::to_string(&serde_json::json!({
"id": completion_id,
"object": "chat.completion.chunk",
"created": now_unix(),
"model": model_name,
"choices": [{
"index": 0,
"delta": {},
"finish_reason": "stop",
}],
})).unwrap_or_default()));
let mitm = state.mitm_store.take_usage(&cascade_id).await
.or(state.mitm_store.take_usage("_latest").await);
let fr = google_to_openai_finish_reason(mitm.as_ref().and_then(|u| u.stop_reason.as_deref()));
yield Ok(Event::default().data(chunk_json(
&completion_id, &model_name,
serde_json::json!([chunk_choice(0, serde_json::json!({}), Some(fr))]),
None,
)));
if include_usage {
let mitm = state.mitm_store.take_usage(&cascade_id).await
.or(state.mitm_store.take_usage("_latest").await);
let (pt, ct, crt, tt) = if let Some(ref u) = mitm {
(u.input_tokens, u.output_tokens, u.cache_read_input_tokens, u.thinking_output_tokens)
} else { (0, 0, 0, 0) };
yield Ok(Event::default().data(serde_json::to_string(&serde_json::json!({
"id": completion_id,
"object": "chat.completion.chunk",
"created": now_unix(),
"model": model_name,
"choices": [],
"usage": {
"prompt_tokens": pt,
"completion_tokens": ct,
"total_tokens": pt + ct,
"prompt_tokens_details": { "cached_tokens": crt },
"completion_tokens_details": { "reasoning_tokens": tt },
},
})).unwrap_or_default()));
yield Ok(Event::default().data(chunk_json(
&completion_id, &model_name,
serde_json::json!([]),
Some(build_usage(pt, ct, crt, tt)),
)));
}
yield Ok(Event::default().data("[DONE]"));
return;
@@ -673,37 +757,23 @@ async fn chat_completions_stream(
let run_status = td["status"].as_str().unwrap_or("");
if run_status.contains("IDLE") && !last_text.is_empty() {
debug!("Completions IDLE, text length={}", last_text.len());
yield Ok(Event::default().data(serde_json::to_string(&serde_json::json!({
"id": completion_id,
"object": "chat.completion.chunk",
"created": now_unix(),
"model": model_name,
"choices": [{
"index": 0,
"delta": {},
"finish_reason": "stop",
}],
})).unwrap_or_default()));
let mitm = state.mitm_store.take_usage(&cascade_id).await
.or(state.mitm_store.take_usage("_latest").await);
let fr = google_to_openai_finish_reason(mitm.as_ref().and_then(|u| u.stop_reason.as_deref()));
yield Ok(Event::default().data(chunk_json(
&completion_id, &model_name,
serde_json::json!([chunk_choice(0, serde_json::json!({}), Some(fr))]),
None,
)));
if include_usage {
let mitm = state.mitm_store.take_usage(&cascade_id).await
.or(state.mitm_store.take_usage("_latest").await);
let (pt, ct, crt, tt) = if let Some(ref u) = mitm {
(u.input_tokens, u.output_tokens, u.cache_read_input_tokens, u.thinking_output_tokens)
} else { (0, 0, 0, 0) };
yield Ok(Event::default().data(serde_json::to_string(&serde_json::json!({
"id": completion_id,
"object": "chat.completion.chunk",
"created": now_unix(),
"model": model_name,
"choices": [],
"usage": {
"prompt_tokens": pt,
"completion_tokens": ct,
"total_tokens": pt + ct,
"prompt_tokens_details": { "cached_tokens": crt },
"completion_tokens_details": { "reasoning_tokens": tt },
},
})).unwrap_or_default()));
yield Ok(Event::default().data(chunk_json(
&completion_id, &model_name,
serde_json::json!([]),
Some(build_usage(pt, ct, crt, tt)),
)));
}
yield Ok(Event::default().data("[DONE]"));
return;
@@ -728,37 +798,23 @@ async fn chat_completions_stream(
// Timeout
warn!("Completions stream timeout after {}s", timeout);
yield Ok(Event::default().data(serde_json::to_string(&serde_json::json!({
"id": completion_id,
"object": "chat.completion.chunk",
"created": now_unix(),
"model": model_name,
"choices": [{
"index": 0,
"delta": {"content": if last_text.is_empty() { "[Timeout waiting for response]" } else { "" }},
"finish_reason": "stop",
}],
})).unwrap_or_default()));
let mitm = state.mitm_store.take_usage(&cascade_id).await
.or(state.mitm_store.take_usage("_latest").await);
let fr = google_to_openai_finish_reason(mitm.as_ref().and_then(|u| u.stop_reason.as_deref()));
yield Ok(Event::default().data(chunk_json(
&completion_id, &model_name,
serde_json::json!([chunk_choice(0, serde_json::json!({"content": if last_text.is_empty() { "[Timeout waiting for response]" } else { "" }}), Some(fr))]),
None,
)));
if include_usage {
let mitm = state.mitm_store.take_usage(&cascade_id).await
.or(state.mitm_store.take_usage("_latest").await);
let (pt, ct, crt, tt) = if let Some(ref u) = mitm {
(u.input_tokens, u.output_tokens, u.cache_read_input_tokens, u.thinking_output_tokens)
} else { (0, 0, 0, 0) };
yield Ok(Event::default().data(serde_json::to_string(&serde_json::json!({
"id": completion_id,
"object": "chat.completion.chunk",
"created": now_unix(),
"model": model_name,
"choices": [],
"usage": {
"prompt_tokens": pt,
"completion_tokens": ct,
"total_tokens": pt + ct,
"prompt_tokens_details": { "cached_tokens": crt },
"completion_tokens_details": { "reasoning_tokens": tt },
},
})).unwrap_or_default()));
yield Ok(Event::default().data(chunk_json(
&completion_id, &model_name,
serde_json::json!([]),
Some(build_usage(pt, ct, crt, tt)),
)));
}
yield Ok(Event::default().data("[DONE]"));
};
@@ -789,7 +845,10 @@ async fn chat_completions_sync(
Some(u) => Some(u),
None => state.mitm_store.take_usage("_latest").await,
};
let (prompt_tokens, completion_tokens, cached_tokens, thinking_tokens) = if let Some(mitm_usage) = mitm {
let finish_reason = google_to_openai_finish_reason(mitm.as_ref().and_then(|u| u.stop_reason.as_deref()));
let (prompt_tokens, completion_tokens, cached_tokens, thinking_tokens) = if let Some(ref mitm_usage) = mitm {
(mitm_usage.input_tokens, mitm_usage.output_tokens, mitm_usage.cache_read_input_tokens, mitm_usage.thinking_output_tokens)
} else if let Some(u) = &result.usage {
(u.input_tokens, u.output_tokens, 0, 0)
@@ -811,10 +870,13 @@ async fn chat_completions_sync(
"object": "chat.completion",
"created": now_unix(),
"model": model_name,
"system_fingerprint": system_fingerprint(),
"service_tier": "default",
"choices": [{
"index": 0,
"message": message,
"finish_reason": "stop",
"logprobs": serde_json::Value::Null,
"finish_reason": finish_reason,
}],
"usage": {
"prompt_tokens": prompt_tokens,

View File

@@ -57,6 +57,14 @@ pub(crate) struct GeminiRequest {
/// Stop sequences.
#[serde(default, alias = "stopSequences")]
pub stop_sequences: Option<Vec<String>>,
/// Thinking level for Gemini 3 models: "minimal", "low", "medium", "high".
/// Maps directly to thinkingConfig.thinkingLevel.
#[serde(default, alias = "thinkingLevel")]
pub thinking_level: Option<String>,
/// Enable Google Search grounding. See Gemini API docs.
/// When true, injects {"googleSearch": {}} into tools via MITM.
#[serde(default, alias = "googleSearch")]
pub google_search: bool,
}
fn default_timeout() -> u64 {
@@ -130,10 +138,33 @@ pub(crate) async fn handle_gemini(
// Extract user text
let user_text = match &body.input {
serde_json::Value::String(s) => s.clone(),
serde_json::Value::Array(arr) => {
// Support array input: can be strings or {text: "..."} objects
let mut parts: Vec<String> = Vec::new();
for item in arr {
match item {
serde_json::Value::String(s) => parts.push(s.clone()),
serde_json::Value::Object(obj) => {
if let Some(text) = obj.get("text").and_then(|v| v.as_str()) {
parts.push(text.to_string());
}
}
_ => {}
}
}
if parts.is_empty() {
return err_response(
StatusCode::BAD_REQUEST,
"Gemini input array contains no text parts".to_string(),
"invalid_request_error",
);
}
parts.join("\n")
}
_ => {
return err_response(
StatusCode::BAD_REQUEST,
"Gemini endpoint requires input as a string".to_string(),
"Gemini endpoint requires input as a string or array of text parts".to_string(),
"invalid_request_error",
);
}
@@ -176,9 +207,14 @@ pub(crate) async fn handle_gemini(
stop_sequences: body.stop_sequences.clone(),
frequency_penalty: None,
presence_penalty: None,
reasoning_effort: body.thinking_level.clone(),
response_mime_type: None,
response_schema: None,
google_search: body.google_search,
};
if gp.temperature.is_some() || gp.top_p.is_some() || gp.top_k.is_some()
|| gp.max_output_tokens.is_some() || gp.stop_sequences.is_some()
|| gp.reasoning_effort.is_some() || gp.google_search
{
state.mitm_store.set_generation_params(gp).await;
} else {
@@ -443,6 +479,7 @@ async fn gemini_stream(
})
.collect();
let usage_meta = build_usage_metadata(&state.mitm_store, &cascade_id).await;
yield Ok::<_, std::convert::Infallible>(Event::default().data(serde_json::to_string(&serde_json::json!({
"candidates": [{
"content": {
@@ -451,6 +488,7 @@ async fn gemini_stream(
},
"finishReason": "STOP",
}],
"usageMetadata": usage_meta,
"modelVersion": model_name,
})).unwrap_or_default()));
yield Ok(Event::default().data("[DONE]"));
@@ -499,7 +537,8 @@ async fn gemini_stream(
// Check completion
let complete = state.mitm_store.is_response_complete();
if complete && !last_text.is_empty() {
// Final chunk with finishReason
// Final chunk with finishReason + usageMetadata
let usage_meta = build_usage_metadata(&state.mitm_store, &cascade_id).await;
yield Ok(Event::default().data(serde_json::to_string(&serde_json::json!({
"candidates": [{
"content": {
@@ -508,6 +547,7 @@ async fn gemini_stream(
},
"finishReason": "STOP",
}],
"usageMetadata": usage_meta,
"modelVersion": model_name,
})).unwrap_or_default()));
yield Ok(Event::default().data("[DONE]"));
@@ -570,6 +610,7 @@ async fn gemini_stream(
// Done check
if is_response_done(steps) && !last_text.is_empty() {
let usage_meta = build_usage_metadata(&state.mitm_store, &cascade_id).await;
yield Ok(Event::default().data(serde_json::to_string(&serde_json::json!({
"candidates": [{
"content": {
@@ -578,6 +619,7 @@ async fn gemini_stream(
},
"finishReason": "STOP",
}],
"usageMetadata": usage_meta,
"modelVersion": model_name,
})).unwrap_or_default()));
yield Ok(Event::default().data("[DONE]"));

View File

@@ -142,12 +142,15 @@ fn build_response_object(data: ResponseData, params: &RequestParams) -> Response
output: data.output,
parallel_tool_calls: true,
previous_response_id: params.previous_response_id.clone(),
reasoning: Reasoning::default(),
reasoning: Reasoning {
effort: params.reasoning_effort.clone(),
summary: None,
},
store: params.store,
temperature: params.temperature,
text: TextFormat::default(),
tool_choice: "auto",
tools: vec![],
text: params.text_format.clone(),
tool_choice: params.tool_choice.clone(),
tools: params.tools.clone(),
top_p: params.top_p,
truncation: "disabled",
usage: data.usage,
@@ -230,6 +233,13 @@ pub(crate) async fn handle_responses(
}
// Store client tools in MitmStore for MITM injection
// Detect web_search_preview tool (OpenAI spec) → enable Google Search grounding
let has_web_search = body.tools.as_ref().map_or(false, |tools| {
tools.iter().any(|t| {
let t_type = t["type"].as_str().unwrap_or("");
t_type == "web_search_preview" || t_type == "web_search"
})
});
if let Some(ref tools) = body.tools {
let gemini_tools = openai_tools_to_gemini(tools);
if !gemini_tools.is_empty() {
@@ -243,6 +253,28 @@ pub(crate) async fn handle_responses(
}
// Store generation parameters for MITM injection
// Extract text.format for structured output (json_schema)
let (response_mime_type, response_schema, text_format) = if let Some(ref text_val) = body.text {
let fmt_type = text_val["format"]["type"].as_str().unwrap_or("text");
if fmt_type == "json_schema" {
let name = text_val["format"]["name"].as_str().map(|s| s.to_string());
let schema = text_val["format"]["schema"].as_object().map(|o| serde_json::Value::Object(o.clone()));
let strict = text_val["format"]["strict"].as_bool();
let tf = TextFormat {
format: TextFormatInner {
format_type: "json_schema".to_string(),
name: name.clone(),
schema: schema.clone(),
strict,
},
};
(Some("application/json".to_string()), schema, tf)
} else {
(None, None, TextFormat::default())
}
} else {
(None, None, TextFormat::default())
};
{
use crate::mitm::store::GenerationParams;
let gp = GenerationParams {
@@ -253,8 +285,15 @@ pub(crate) async fn handle_responses(
stop_sequences: None,
frequency_penalty: None,
presence_penalty: None,
reasoning_effort: body.reasoning_effort.clone(),
response_mime_type,
response_schema,
google_search: has_web_search,
};
if gp.temperature.is_some() || gp.top_p.is_some() || gp.max_output_tokens.is_some() {
if gp.temperature.is_some() || gp.top_p.is_some() || gp.max_output_tokens.is_some()
|| gp.reasoning_effort.is_some() || gp.response_mime_type.is_some()
|| gp.response_schema.is_some() || gp.google_search
{
state.mitm_store.set_generation_params(gp).await;
} else {
state.mitm_store.clear_generation_params().await;
@@ -337,6 +376,11 @@ pub(crate) async fn handle_responses(
previous_response_id: body.previous_response_id.clone(),
user: body.user.clone(),
metadata: body.metadata.clone().unwrap_or(serde_json::json!({})),
max_tool_calls: body.max_tool_calls,
reasoning_effort: body.reasoning_effort.clone(),
tool_choice: body.tool_choice.clone().unwrap_or(serde_json::json!("auto")),
tools: body.tools.clone().unwrap_or_default(),
text_format,
};
if body.stream {
@@ -365,6 +409,11 @@ struct RequestParams {
previous_response_id: Option<String>,
user: Option<String>,
metadata: serde_json::Value,
max_tool_calls: Option<u32>,
reasoning_effort: Option<String>,
tool_choice: serde_json::Value,
tools: Vec<serde_json::Value>,
text_format: TextFormat,
}
/// Build Usage from the best available source, and extract thinking text from MITM:
@@ -471,10 +520,15 @@ async fn handle_responses_sync(
while start.elapsed().as_secs() < timeout {
// Check for function calls
let captured = state.mitm_store.take_any_function_calls().await;
if let Some(ref calls) = captured {
if let Some(ref raw_calls) = captured {
let calls: Vec<_> = if let Some(max) = params.max_tool_calls {
raw_calls.iter().take(max as usize).collect()
} else {
raw_calls.iter().collect()
};
if !calls.is_empty() {
let mut output_items: Vec<serde_json::Value> = Vec::new();
for fc in calls {
for fc in &calls {
let call_id = format!(
"call_{}",
uuid::Uuid::new_v4().to_string().replace('-', "")[..24].to_string()
@@ -567,6 +621,14 @@ async fn handle_responses_sync(
// Check for captured function calls from MITM (clears the active flag)
let captured_tool_calls = state.mitm_store.take_any_function_calls().await;
// Enforce max_tool_calls limit
let captured_tool_calls = captured_tool_calls.map(|mut calls| {
if let Some(max) = params.max_tool_calls {
calls.truncate(max as usize);
}
calls
});
// If we have captured tool calls, return them as function_call output items
if let Some(ref calls) = captured_tool_calls {
info!(
@@ -714,7 +776,12 @@ async fn handle_responses_stream(
while start.elapsed().as_secs() < timeout {
// Check for function calls first
let captured = state.mitm_store.take_any_function_calls().await;
if let Some(ref calls) = captured {
if let Some(ref raw_calls) = captured {
let calls: Vec<_> = if let Some(max) = params.max_tool_calls {
raw_calls.iter().take(max as usize).collect()
} else {
raw_calls.iter().collect()
};
if !calls.is_empty() {
let msg_output_index: u32 = if thinking_emitted { 1 } else { 0 };
for (i, fc) in calls.iter().enumerate() {
@@ -762,7 +829,7 @@ async fn handle_responses_stream(
// Build output for final response
let mut output_items: Vec<serde_json::Value> = Vec::new();
for fc in calls {
for fc in &calls {
let call_id = format!(
"call_{}",
uuid::Uuid::new_v4().to_string().replace('-', "")[..24].to_string()

288
src/api/search.rs Normal file
View File

@@ -0,0 +1,288 @@
//! Pure search endpoint (/v1/search) — triggers Google Search via the LS.
//!
//! Sends a minimal prompt to the LS with Google Search grounding enabled,
//! captures the grounding metadata from the response, and returns the
//! search results without the model's generated text.
//!
//! The LS triggers the actual search request to Google's servers;
//! we capture the results via MITM, never calling Google directly.
use axum::{
extract::State,
http::StatusCode,
response::{IntoResponse, Json},
};
use std::sync::Arc;
use tracing::{info, warn};
use super::models::{lookup_model, MODELS};
use super::polling::poll_for_response;
use super::util::err_response;
use super::AppState;
/// Search request body.
#[derive(serde::Deserialize)]
pub(crate) struct SearchRequest {
/// Search query.
pub query: String,
/// Model to use for grounding. Defaults to gemini-3-flash (cheapest).
#[serde(default = "default_search_model")]
pub model: String,
/// Timeout in seconds.
#[serde(default = "default_search_timeout")]
pub timeout: u64,
/// Conversation/session ID for context reuse.
#[serde(default)]
pub conversation: Option<String>,
/// Max output tokens — keep low since we only want grounding metadata.
#[serde(default = "default_search_max_tokens")]
pub max_output_tokens: u64,
}
fn default_search_model() -> String {
"gemini-3-flash".to_string()
}
fn default_search_timeout() -> u64 {
30
}
fn default_search_max_tokens() -> u64 {
256
}
/// GET /v1/search?q=... — quick search via query param.
pub(crate) async fn handle_search_get(
State(state): State<Arc<AppState>>,
axum::extract::Query(params): axum::extract::Query<SearchQueryParams>,
) -> axum::response::Response {
info!("GET /v1/search q={}", params.q);
let body = SearchRequest {
query: params.q,
model: params.model.unwrap_or_else(default_search_model),
timeout: params.timeout.unwrap_or(default_search_timeout()),
conversation: None,
max_output_tokens: params.max_tokens.unwrap_or(default_search_max_tokens()),
};
do_search(state, body).await
}
#[derive(serde::Deserialize)]
pub(crate) struct SearchQueryParams {
pub q: String,
#[serde(default)]
pub model: Option<String>,
#[serde(default)]
pub timeout: Option<u64>,
#[serde(default)]
pub max_tokens: Option<u64>,
}
/// POST /v1/search — full search request.
pub(crate) async fn handle_search_post(
State(state): State<Arc<AppState>>,
Json(body): Json<SearchRequest>,
) -> axum::response::Response {
info!("POST /v1/search q={}", body.query);
do_search(state, body).await
}
async fn do_search(state: Arc<AppState>, body: SearchRequest) -> axum::response::Response {
let model = match lookup_model(&body.model) {
Some(m) => m,
None => {
let names: Vec<&str> = MODELS.iter().map(|m| m.name).collect();
return err_response(
StatusCode::BAD_REQUEST,
format!("Unknown model: {}. Available: {names:?}", body.model),
"invalid_request_error",
);
}
};
let token = state.backend.oauth_token().await;
if token.is_empty() {
return err_response(
StatusCode::UNAUTHORIZED,
"No OAuth token.".into(),
"authentication_error",
);
}
// Enable Google Search grounding via GenerationParams
{
use crate::mitm::store::GenerationParams;
let gp = GenerationParams {
max_output_tokens: Some(body.max_output_tokens),
google_search: true,
..Default::default()
};
state.mitm_store.set_generation_params(gp).await;
}
// Clear any stale tools — we only want googleSearch
state.mitm_store.clear_tools().await;
// Create a prompt that encourages the model to ground its response
let search_prompt = format!(
"Search the web for the following query and provide a brief summary of the results:\n\n{}",
body.query
);
// Session management
let session_id_str = body.conversation.clone();
let cascade_id = if let Some(ref sid) = session_id_str {
match state
.sessions
.get_or_create(Some(sid), || state.backend.create_cascade())
.await
{
Ok(sr) => sr.cascade_id,
Err(e) => {
return err_response(
StatusCode::INTERNAL_SERVER_ERROR,
format!("Failed to create session: {e}"),
"server_error",
);
}
}
} else {
match state.backend.create_cascade().await {
Ok(id) => id,
Err(e) => {
return err_response(
StatusCode::INTERNAL_SERVER_ERROR,
format!("Failed to create cascade: {e}"),
"server_error",
);
}
}
};
// Set active cascade for MITM correlation
state.mitm_store.set_active_cascade(&cascade_id).await;
// Send the search message
if let Err(e) = state
.backend
.send_message(&cascade_id, &search_prompt, model.model_enum)
.await
{
state.mitm_store.clear_active_cascade().await;
state.mitm_store.clear_generation_params().await;
return err_response(
StatusCode::INTERNAL_SERVER_ERROR,
format!("Failed to send search message: {e}"),
"server_error",
);
}
// Poll for response
let poll_result = poll_for_response(&state, &cascade_id, body.timeout).await;
// Extract grounding metadata
let grounding = state.mitm_store.take_grounding().await;
// The poll result text contains the model's summary (grounded response)
let response_text = if !poll_result.text.is_empty() {
poll_result.text.clone()
} else {
// Fall back to MITM captured text
state.mitm_store.take_response_text().await.unwrap_or_default()
};
// Clean up
state.mitm_store.clear_active_cascade().await;
state.mitm_store.clear_generation_params().await;
state.mitm_store.clear_response_async().await;
// Build the search response
let mut response = serde_json::json!({
"object": "search_result",
"query": body.query,
"model": model.name,
"summary": response_text,
});
// Include grounding metadata if available
if let Some(ref gm) = grounding {
// Extract structured search results
let mut search_results = Vec::new();
// groundingChunks → individual web results
if let Some(chunks) = gm.get("groundingChunks").and_then(|v| v.as_array()) {
for chunk in chunks {
if let Some(web) = chunk.get("web") {
search_results.push(serde_json::json!({
"title": web.get("title").and_then(|v| v.as_str()).unwrap_or(""),
"url": web.get("uri").and_then(|v| v.as_str()).unwrap_or(""),
}));
}
}
}
// groundingSupports → citations with source references
let mut citations = Vec::new();
if let Some(supports) = gm.get("groundingSupports").and_then(|v| v.as_array()) {
for support in supports {
let text = support.get("segment")
.and_then(|s| s.get("text"))
.and_then(|v| v.as_str())
.unwrap_or("");
let indices: Vec<u64> = support.get("groundingChunkIndices")
.and_then(|v| v.as_array())
.map(|arr| arr.iter().filter_map(|i| i.as_u64()).collect())
.unwrap_or_default();
let scores: Vec<f64> = support.get("confidenceScores")
.and_then(|v| v.as_array())
.map(|arr| arr.iter().filter_map(|s| s.as_f64()).collect())
.unwrap_or_default();
citations.push(serde_json::json!({
"text": text,
"source_indices": indices,
"confidence_scores": scores,
}));
}
}
// searchEntryPoint → rendered search widget HTML
let search_url = gm.get("searchEntryPoint")
.and_then(|sep| sep.get("renderedContent"))
.and_then(|v| v.as_str());
// webSearchQueries → the actual queries Google used
let queries = gm.get("webSearchQueries")
.and_then(|v| v.as_array())
.map(|arr| arr.iter().filter_map(|q| q.as_str().map(|s| s.to_string())).collect::<Vec<_>>());
response["results"] = serde_json::json!(search_results);
response["citations"] = serde_json::json!(citations);
if let Some(qs) = queries {
response["search_queries"] = serde_json::json!(qs);
}
if let Some(url) = search_url {
response["search_widget_html"] = serde_json::json!(url);
}
// Include raw grounding metadata for advanced consumers
response["grounding_metadata"] = gm.clone();
} else {
response["results"] = serde_json::json!([]);
response["citations"] = serde_json::json!([]);
warn!("Search completed but no grounding metadata captured — model may not have grounded");
}
// Include usage if available
if let Some(ref u) = poll_result.usage {
response["usage"] = serde_json::json!({
"input_tokens": u.input_tokens,
"output_tokens": u.output_tokens,
"total_tokens": u.input_tokens + u.output_tokens,
});
}
Json(response).into_response()
}

View File

@@ -38,6 +38,17 @@ pub(crate) struct ResponsesRequest {
/// Tool choice: "auto", "required", "none", or {"type":"function","function":{"name":"X"}}.
#[serde(default)]
pub tool_choice: Option<serde_json::Value>,
/// Reasoning effort — forwarded as thinkingConfig.thinkingLevel to Google.
/// Values: "low", "medium", "high".
#[serde(default)]
pub reasoning_effort: Option<String>,
/// Maximum number of tool calls allowed per response.
#[serde(default)]
pub max_tool_calls: Option<u32>,
/// Text output format — {format: {type: "json_schema", name: "...", schema: {...}}}.
/// When json_schema, injects responseMimeType + responseSchema via MITM.
#[serde(default)]
pub text: Option<serde_json::Value>,
}
/// Stream options for Chat Completions (controls usage emission in final chunk).
@@ -85,6 +96,80 @@ pub(crate) struct CompletionRequest {
/// Presence penalty — forwarded to Google via MITM.
#[serde(default)]
pub presence_penalty: Option<f64>,
/// Reasoning effort — forwarded as thinkingConfig.thinkingLevel to Google.
/// Values: "low", "medium", "high".
#[serde(default)]
pub reasoning_effort: Option<String>,
/// Stop sequences — forwarded as generationConfig.stopSequences to Google.
/// Up to 4 sequences where the API will stop generating further tokens.
#[serde(default)]
pub stop: Option<StopSequence>,
/// Response format — {"type": "json_object"} or {"type": "json_schema", "json_schema": {...}}.
/// Injected as responseMimeType (+ responseSchema) in generationConfig via MITM.
#[serde(default)]
pub response_format: Option<ResponseFormat>,
/// Session/conversation ID for multi-turn reuse (custom extension).
#[serde(default)]
pub conversation: Option<serde_json::Value>,
/// Metadata — accepted and ignored (no upstream equivalent).
#[serde(default)]
pub metadata: Option<serde_json::Value>,
/// Number of completions to generate. Each uses a separate cascade (costs N× quota).
/// Defaults to 1. Only supported in sync mode; streaming always uses n=1.
#[serde(default = "default_n")]
pub n: u32,
/// Enable Google Search grounding. When true, the model can search the web
/// and responses include grounding metadata with search results/citations.
#[serde(default)]
pub web_search: bool,
}
fn default_n() -> u32 { 1 }
/// Stop sequence can be a single string or array of strings (OpenAI accepts both).
#[derive(Deserialize, Clone)]
#[serde(untagged)]
pub(crate) enum StopSequence {
Single(String),
Multiple(Vec<String>),
}
impl StopSequence {
pub fn into_vec(self) -> Vec<String> {
match self {
StopSequence::Single(s) => vec![s],
StopSequence::Multiple(v) => v,
}
}
}
/// Response format for structured output.
/// Supports:
/// - `{"type": "json_object"}` — JSON mode (responseMimeType only)
/// - `{"type": "json_schema", "json_schema": {"name": "...", "schema": {...}}}` — structured output (responseMimeType + responseSchema)
/// - `{"type": "text"}` — plain text (default, no injection)
#[derive(Deserialize, Clone)]
pub(crate) struct ResponseFormat {
#[serde(rename = "type")]
pub format_type: String,
/// JSON schema definition for structured output.
/// Only used when format_type is "json_schema".
#[serde(default)]
pub json_schema: Option<JsonSchemaFormat>,
}
/// JSON schema structured output format.
#[derive(Deserialize, Clone)]
pub(crate) struct JsonSchemaFormat {
/// Schema name (for client identification).
#[serde(default)]
pub name: Option<String>,
/// The actual JSON schema object — forwarded as Gemini's responseSchema.
#[serde(default)]
pub schema: Option<serde_json::Value>,
/// Whether to enable strict schema adherence.
#[serde(default)]
pub strict: Option<bool>,
}
#[derive(Deserialize)]
@@ -132,7 +217,7 @@ pub(crate) struct ResponsesResponse {
pub store: bool,
pub temperature: f64,
pub text: TextFormat,
pub tool_choice: &'static str,
pub tool_choice: serde_json::Value,
pub tools: Vec<serde_json::Value>,
pub top_p: f64,
pub truncation: &'static str,
@@ -180,7 +265,16 @@ pub(crate) struct TextFormat {
#[derive(Serialize, Clone)]
pub(crate) struct TextFormatInner {
#[serde(rename = "type")]
pub format_type: &'static str,
pub format_type: String,
/// JSON schema — present when format_type is "json_schema".
#[serde(skip_serializing_if = "Option::is_none")]
pub name: Option<String>,
/// The actual schema object.
#[serde(skip_serializing_if = "Option::is_none")]
pub schema: Option<serde_json::Value>,
/// Whether strict mode was requested.
#[serde(skip_serializing_if = "Option::is_none")]
pub strict: Option<bool>,
}
impl Usage {
@@ -220,7 +314,10 @@ impl Default for TextFormat {
fn default() -> Self {
Self {
format: TextFormatInner {
format_type: "text",
format_type: "text".to_string(),
name: None,
schema: None,
strict: None,
},
}
}

View File

@@ -755,7 +755,7 @@ async fn handle_http_over_tls(
info!("MITM: stored {} function call(s) from initial body", streaming_acc.function_calls.len());
}
// Capture response + thinking text directly into MitmStore
// Capture response + thinking text + grounding directly into MitmStore
if bypass_ls {
if !streaming_acc.response_text.is_empty() {
store.set_response_text(&streaming_acc.response_text).await;
@@ -763,6 +763,9 @@ async fn handle_http_over_tls(
if !streaming_acc.thinking_text.is_empty() {
store.set_thinking_text(&streaming_acc.thinking_text).await;
}
if let Some(ref gm) = streaming_acc.grounding_metadata {
store.set_grounding(gm.clone()).await;
}
if streaming_acc.is_complete {
store.mark_response_complete();
}
@@ -827,7 +830,7 @@ async fn handle_http_over_tls(
info!("MITM: stored {} function call(s) from body chunk", streaming_acc.function_calls.len());
}
// Capture response + thinking text directly into MitmStore
// Capture response + thinking text + grounding directly into MitmStore
if bypass_ls {
if !streaming_acc.response_text.is_empty() {
store.set_response_text(&streaming_acc.response_text).await;
@@ -835,6 +838,9 @@ async fn handle_http_over_tls(
if !streaming_acc.thinking_text.is_empty() {
store.set_thinking_text(&streaming_acc.thinking_text).await;
}
if let Some(ref gm) = streaming_acc.grounding_metadata {
store.set_grounding(gm.clone()).await;
}
if streaming_acc.is_complete {
store.mark_response_complete();
}
@@ -883,6 +889,10 @@ async fn handle_http_over_tls(
// Capture usage data
if is_streaming_response {
// Store grounding metadata before consuming the accumulator
if let Some(ref gm) = streaming_acc.grounding_metadata {
store.set_grounding(gm.clone()).await;
}
if streaming_acc.is_complete || streaming_acc.output_tokens > 0 {
// Function calls are stored immediately when detected (above),
// so no need to store them again here.