feat: Add get_proxy_host_logs tool for reading nginx proxy host logs

Reads nginx access/error logs directly from a mounted NPM log directory,
enabling agents to debug proxy issues without SSH access. Requires mounting
NPM's /data/logs volume and setting NPM_LOG_DIR.

Also includes a feature request PRD for proposing a native log API upstream.

README.md

@@ -64,6 +64,7 @@ NPM_PROXY_DEFAULTS='{"certificate_id": 24, "ssl_forced": true}'
 | `NPM_MCP_HOST` | No | `0.0.0.0` | MCP server bind address |
 | `NPM_MCP_PORT` | No | `8000` | MCP server port |
 | `NPM_MCP_TRANSPORT` | No | `stdio` | Transport mode (`stdio` or `http`) |
+| `NPM_LOG_DIR` | No | - | Path to mounted NPM log directory (enables `get_proxy_host_logs`) |
 | `NPM_PROXY_DEFAULTS` | No | `{}` | JSON defaults for `create_proxy_host` |
 
 ### NPM_PROXY_DEFAULTS Keys
@@ -126,6 +127,7 @@ Add to your `claude_desktop_config.json`:
 |------|-------------|
 | `list_proxy_hosts` | List all proxy hosts |
 | `get_proxy_host_details` | Get full config for a specific host |
+| `get_proxy_host_logs` | Retrieve nginx access/error logs for a proxy host (requires log mount) |
 | `get_system_health` | Check NPM version and status |
 | `search_audit_logs` | Query audit log entries |
 | `list_certificates` | List SSL certificates |
@@ -134,6 +136,93 @@ Add to your `claude_desktop_config.json`:
 | `update_proxy_host` | Update an existing proxy host (v0.0.3+) |
 | `create_certificate` | Provision a new Let's Encrypt SSL certificate (v0.0.3+) |
 
+## Log Access Setup
+
+The `get_proxy_host_logs` tool reads nginx log files directly from disk. Since NPM has no API for log retrieval, you need to mount NPM's log directory into the MCP container.
+
+NPM writes per-host logs to `/data/logs/` inside its container:
+- `proxy-host-{id}_access.log` — HTTP request log (client IP, status, path, user agent)
+- `proxy-host-{id}_error.log` — nginx error log (upstream failures, config issues)
+
+### Docker Compose (same stack)
+
+If NPM and the MCP server share a compose stack with a named volume:
+
+```yaml
+services:
+  nginx-proxy-manager:
+    image: jc21/nginx-proxy-manager:latest
+    volumes:
+      - npm_data:/data
+
+  npm-mcp:
+    image: ghcr.io/b3nw/nginx-proxy-manager-mcp:latest
+    environment:
+      - NPM_API_URL=http://nginx-proxy-manager:81/api
+      - NPM_IDENTITY=admin@example.com
+      - NPM_SECRET=yourpassword
+      - NPM_LOG_DIR=/data/npm-logs
+    volumes:
+      # Mount NPM's /data volume — logs are in /data/logs/ inside it
+      - npm_data:/data/npm-logs:ro
+    depends_on:
+      - nginx-proxy-manager
+
+volumes:
+  npm_data:
+```
+
+> **Note:** NPM stores logs under `/data/logs/` inside its data volume. When you
+> mount the full `/data` volume to `/data/npm-logs`, the MCP server looks for logs at
+> `/data/npm-logs/logs/`. Set `NPM_LOG_DIR` to match your mount path plus `/logs`.
+
+If you mounted the full data volume:
+
+```bash
+NPM_LOG_DIR=/data/npm-logs/logs
+```
+
+### Bind Mount (separate stacks)
+
+If NPM uses a bind mount (e.g., `./npm-data:/data`), mount the logs subdirectory directly:
+
+```yaml
+npm-mcp:
+  volumes:
+    - /path/to/npm-data/logs:/data/npm-logs:ro
+  environment:
+    - NPM_LOG_DIR=/data/npm-logs
+```
+
+### Docker Run
+
+```bash
+docker run -d \
+  --name npm-mcp \
+  -p 8000:8000 \
+  -v npm_data:/data/npm-logs:ro \
+  -e NPM_API_URL=http://your-npm:81/api \
+  -e NPM_IDENTITY=admin@example.com \
+  -e NPM_SECRET=yourpassword \
+  -e NPM_LOG_DIR=/data/npm-logs/logs \
+  -e NPM_MCP_TRANSPORT=http \
+  ghcr.io/b3nw/nginx-proxy-manager-mcp:latest
+```
+
+### Local Development (non-Docker)
+
+Point `NPM_LOG_DIR` at wherever NPM's logs are on your filesystem:
+
+```bash
+NPM_LOG_DIR=/path/to/npm/data/logs npm-mcp
+```
+
+### Verifying the Mount
+
+After starting, call `get_system_health` — if the log directory is mounted and accessible
+the tool will confirm it. You can also call `get_proxy_host_logs` with any host ID to
+verify logs are readable.
+
 ## Development
 
 ```bash

compose.yaml

@@ -16,6 +16,11 @@ services:
       - NPM_MCP_TRANSPORT=http
       - NPM_MCP_HOST=0.0.0.0
       - NPM_MCP_PORT=8000
+      # Optional: Log access (requires volume mount below)
+      # - NPM_LOG_DIR=/data/npm-logs
+    # volumes:
+    #   # Mount NPM's log directory for get_proxy_host_logs tool (read-only)
+    #   - npm_data:/data/npm-logs:ro    # named volume — see "Log Access" in README
     # Uncomment to use .env file instead of inline environment
     # env_file:
     #   - .env
@@ -26,7 +31,7 @@ services:
       retries: 3
       start_period: 10s
 
-# Example: Running alongside NPM in same compose stack
+# Example: Running alongside NPM in same compose stack (with log access)
 # services:
 #   nginx-proxy-manager:
 #     image: jc21/nginx-proxy-manager:latest
@@ -44,6 +49,9 @@ services:
 #       - NPM_API_URL=http://nginx-proxy-manager:81/api
 #       - NPM_IDENTITY=admin@example.com
 #       - NPM_SECRET=changeme
+#       - NPM_LOG_DIR=/data/npm-logs
+#     volumes:
+#       - npm_data:/data/npm-logs:ro
 #     depends_on:
 #       - nginx-proxy-manager
 #

docs/feature-request-log-api.md

@@ -0,0 +1,176 @@
+# Feature Request: Per-Host Log Retrieval API
+
+**Project:** [NginxProxyManager/nginx-proxy-manager](https://github.com/NginxProxyManager/nginx-proxy-manager)
+**Type:** Feature Request
+**Status:** Draft PRD
+
+## Problem Statement
+
+Nginx Proxy Manager writes per-host access and error logs to predictable paths on disk
+(`/data/logs/proxy-host-{id}_access.log`, `/data/logs/proxy-host-{id}_error.log`), but
+provides no API to read them. The only log-related API is the audit log (`GET /api/audit-log`),
+which tracks admin configuration changes — not HTTP traffic.
+
+This means operators and automation tools have no programmatic way to:
+
+- Retrieve recent access log entries for a specific proxy host
+- Check error logs when debugging upstream connectivity issues
+- Monitor traffic patterns or detect anomalies through the existing API surface
+
+The only workarounds today are direct filesystem access (requiring volume mounts or
+`docker exec`) or external log aggregation pipelines, both of which add significant
+operational complexity for a task that should be simple.
+
+## Proposed Solution
+
+Add REST API endpoints to retrieve nginx access and error logs for individual proxy hosts.
+
+### New Endpoints
+
+#### `GET /api/nginx/proxy-hosts/{id}/logs`
+
+Retrieve log entries for a specific proxy host.
+
+**Query Parameters:**
+
+| Parameter  | Type   | Default    | Description                                           |
+|------------|--------|------------|-------------------------------------------------------|
+| `type`     | string | `"access"` | Log type: `"access"` or `"error"`                     |
+| `lines`    | int    | `100`      | Number of most recent lines to return (max: `1000`)   |
+| `search`   | string | -          | Filter lines containing this substring                |
+| `since`    | string | -          | ISO 8601 timestamp — only return lines after this time|
+
+**Response (200):**
+
+```json
+{
+  "host_id": 5,
+  "log_type": "access",
+  "file": "proxy-host-5_access.log",
+  "total_lines": 4821,
+  "returned_lines": 100,
+  "lines": [
+    "[01/Jun/2025:14:22:31 +0000] HIT 200 200 - GET https app.example.com \"/api/data\" [Client 10.0.0.1] [Length 1542] [Gzip -] [Sent-to 192.168.1.50] \"Mozilla/5.0\" \"https://app.example.com/\"",
+    "..."
+  ]
+}
+```
+
+**Error Responses:**
+
+| Status | Condition                           |
+|--------|-------------------------------------|
+| 404    | Proxy host not found                |
+| 404    | Log file does not exist             |
+| 403    | User lacks permission for this host |
+
+#### `GET /api/nginx/proxy-hosts/{id}/logs/summary`
+
+Return a statistical summary of recent traffic for a proxy host.
+
+**Response (200):**
+
+```json
+{
+  "host_id": 5,
+  "period": "last_1000_lines",
+  "status_codes": {"200": 812, "301": 45, "404": 23, "500": 3},
+  "top_paths": ["/api/data", "/", "/login"],
+  "top_clients": ["10.0.0.1", "10.0.0.5"],
+  "cache_hit_rate": 0.42,
+  "access_log_size_bytes": 524288,
+  "error_log_size_bytes": 8192
+}
+```
+
+### Permissions
+
+| Permission         | Description                                |
+|--------------------|--------------------------------------------|
+| `proxy-hosts:logs` | Read logs for proxy hosts the user can view |
+
+Admin users can read logs for any host. Non-admin users can only read logs
+for hosts they own, consistent with existing proxy host permissions.
+
+### Backend Implementation Notes
+
+The implementation is straightforward because log paths are already deterministic
+and hardcoded in nginx templates:
+
+```javascript
+// backend/templates/proxy_host.conf
+access_log /data/logs/proxy-host-{{ id }}_access.log proxy;
+error_log /data/logs/proxy-host-{{ id }}_error.log warn;
+```
+
+A minimal implementation would:
+
+1. Add a new route in `backend/routes/` (e.g., `proxy-host-logs.js`)
+2. Verify the proxy host exists and the user has access
+3. Read the last N lines from the log file using a reverse-reader (or `tail`-like approach)
+4. Optionally filter lines by substring or timestamp
+5. Return as JSON
+
+**Reference files for implementation:**
+
+- `backend/routes/nginx/proxy_hosts.js` — existing proxy host routes and permission model
+- `backend/templates/proxy_host.conf` — log path template confirming the naming convention
+- `backend/lib/access/` — permission definition files
+- `docker/rootfs/etc/logrotate.d/nginx-proxy-manager` — log rotation config (rotated logs
+  have `.1`, `.2.gz` suffixes)
+
+### Log Rotation Consideration
+
+NPM rotates logs weekly (access: 4 rotations, error: 10 rotations). The API should
+read only the current (unrotated) log file. Rotated archives (`.1`, `.2.gz`) could be
+supported in a future iteration but are not required for the initial implementation.
+
+## Motivation
+
+### Use Cases
+
+1. **MCP/AI Agent Integration** — MCP servers wrapping the NPM API (like
+   [nginx-proxy-manager-mcp](https://github.com/b3nw/nginx-proxy-manager-mcp)) can
+   expose log retrieval to AI assistants for debugging proxy issues conversationally.
+
+2. **Quick Debugging** — When a reverse proxy returns errors, operators need to quickly
+   check the access and error logs for that specific host. Today this requires SSH/exec
+   access to the container.
+
+3. **Monitoring Dashboards** — Custom dashboards can poll the log endpoint for
+   traffic summaries without deploying a full log aggregation stack.
+
+4. **Automation** — CI/CD pipelines and health-check scripts can verify that traffic
+   is flowing correctly to newly deployed services behind NPM.
+
+### Why Not External Log Aggregation?
+
+External solutions (Loki, ELK, Fluentd) are powerful but heavy. Many NPM users run
+single-host homelab setups where a full log pipeline is disproportionate to the need.
+A built-in API covers 80% of use cases with zero additional infrastructure.
+
+## Alternatives Considered
+
+| Approach                  | Pros                        | Cons                                            |
+|---------------------------|-----------------------------|-------------------------------------------------|
+| **API endpoint (proposed)** | Native, zero extra infra  | Requires upstream PR                            |
+| Volume mount + file read  | Works today, no NPM changes | Tight coupling, no access control, not portable |
+| Docker exec               | Works today                 | Requires Docker socket, security risk           |
+| Sidecar log server        | Decoupled                   | Extra container, extra config, extra maintenance |
+
+## Scope
+
+### In Scope (v1)
+
+- `GET /api/nginx/proxy-hosts/{id}/logs` with `type`, `lines`, `search` params
+- Permission checks consistent with existing proxy host access model
+- Current (unrotated) log file only
+
+### Out of Scope (Future)
+
+- Log streaming via WebSocket or SSE
+- Rotated log archive access (`.gz` files)
+- Log summary/analytics endpoint
+- Redirection host, dead host, and stream logs (same pattern, easy to add later)
+- Log download as file attachment
+- Log retention configuration via API

env.example

@@ -8,6 +8,11 @@ NPM_MCP_HOST=0.0.0.0
 NPM_MCP_PORT=8000
 NPM_MCP_TRANSPORT=stdio  # stdio or http
 
+# Log Access (optional)
+# Mount NPM's /data/logs directory and set this to the mount path.
+# Enables the get_proxy_host_logs tool for reading nginx access/error logs.
+# NPM_LOG_DIR=/data/npm-logs
+
 # Proxy Host Creation Defaults (JSON)
 # Set default values for create_proxy_host tool parameters
 # Example with wildcard cert: NPM_PROXY_DEFAULTS='{"certificate_id": 24, "ssl_forced": true}'

src/npm_mcp/config.py

@@ -42,6 +42,9 @@ class Settings(BaseSettings):
     mcp_port: int = 8000
     mcp_transport: str = "stdio"  # "stdio" or "http"
 
+    # Path to NPM log directory (mount NPM's /data/logs here)
+    log_dir: str = ""
+
     # Proxy host creation defaults (JSON string)
     # Example: '{"certificate_id": 24, "ssl_forced": true}'
     proxy_defaults: dict[str, Any] = {}

src/npm_mcp/exceptions.py

@@ -31,3 +31,9 @@ class NpmApiError(NpmClientError):
     def __init__(self, message: str, status_code: int | None = None):
         super().__init__(message)
         self.status_code = status_code
+
+
+class NpmLogError(NpmClientError):
+    """Raised when log file operations fail."""
+
+    pass

src/npm_mcp/logs.py

@@ -0,0 +1,118 @@
+"""Log file reader for Nginx Proxy Manager proxy host logs."""
+
+from __future__ import annotations
+
+import re
+from pathlib import Path
+
+from .config import settings
+from .exceptions import NpmLogError
+
+LOG_FILE_PATTERN = re.compile(r"^proxy-host-(\d+)_(access|error)\.log$")
+
+MAX_LINES = 500
+MAX_FILE_SIZE = 50 * 1024 * 1024  # 50 MB safety cap
+
+
+def _get_log_dir() -> Path:
+    """Resolve and validate the configured log directory."""
+    log_dir = settings.log_dir
+    if not log_dir:
+        raise NpmLogError(
+            "NPM_LOG_DIR is not configured. Mount NPM's /data/logs volume "
+            "and set NPM_LOG_DIR to the mount path. See README for details."
+        )
+    path = Path(log_dir)
+    if not path.is_dir():
+        raise NpmLogError(f"Log directory does not exist: {log_dir}")
+    return path
+
+
+def _log_file_path(host_id: int, log_type: str) -> Path:
+    if log_type not in ("access", "error"):
+        raise NpmLogError(f"Invalid log type: {log_type!r} (must be 'access' or 'error')")
+    log_dir = _get_log_dir()
+    return log_dir / f"proxy-host-{host_id}_{log_type}.log"
+
+
+def read_log_lines(
+    host_id: int,
+    log_type: str = "access",
+    lines: int = 100,
+    search: str | None = None,
+) -> dict:
+    """Read the last N lines from a proxy host log file.
+
+    Args:
+        host_id: NPM proxy host ID.
+        log_type: "access" or "error".
+        lines: Number of most recent lines to return (capped at MAX_LINES).
+        search: Optional substring filter applied to each line.
+
+    Returns:
+        Dict with host_id, log_type, file name, line count, and the lines themselves.
+    """
+    lines = max(1, min(lines, MAX_LINES))
+    log_path = _log_file_path(host_id, log_type)
+
+    if not log_path.is_file():
+        raise NpmLogError(
+            f"Log file not found: {log_path.name}. "
+            "The proxy host may not have received any traffic yet, "
+            "or the log directory mount is incorrect."
+        )
+
+    file_size = log_path.stat().st_size
+    if file_size > MAX_FILE_SIZE:
+        raise NpmLogError(
+            f"Log file is too large ({file_size / 1024 / 1024:.1f} MB). "
+            "Consider using an external log aggregation tool."
+        )
+
+    all_lines = log_path.read_text(errors="replace").splitlines()
+    total_lines = len(all_lines)
+
+    if search:
+        search_lower = search.lower()
+        all_lines = [line for line in all_lines if search_lower in line.lower()]
+
+    tail = all_lines[-lines:]
+
+    return {
+        "host_id": host_id,
+        "log_type": log_type,
+        "file": log_path.name,
+        "total_lines_in_file": total_lines if not search else None,
+        "matched_lines": len(all_lines) if search else None,
+        "returned_lines": len(tail),
+        "lines": tail,
+    }
+
+
+def is_log_dir_configured() -> bool:
+    """Check whether the log directory is configured and accessible."""
+    if not settings.log_dir:
+        return False
+    return Path(settings.log_dir).is_dir()
+
+
+def list_available_logs() -> list[dict]:
+    """List all proxy-host log files present in the log directory.
+
+    Returns:
+        List of dicts with host_id, log_type, file name, and size.
+    """
+    log_dir = _get_log_dir()
+    results = []
+    for entry in sorted(log_dir.iterdir()):
+        match = LOG_FILE_PATTERN.match(entry.name)
+        if match and entry.is_file():
+            results.append(
+                {
+                    "host_id": int(match.group(1)),
+                    "log_type": match.group(2),
+                    "file": entry.name,
+                    "size_bytes": entry.stat().st_size,
+                }
+            )
+    return results

src/npm_mcp/server.py

@@ -9,7 +9,8 @@ from mcp.server.fastmcp import FastMCP
 
 from .client import NpmClient
 from .config import settings
-from .exceptions import NpmApiError, NpmAuthenticationError, NpmConnectionError
+from .exceptions import NpmApiError, NpmAuthenticationError, NpmConnectionError, NpmLogError
+from .logs import is_log_dir_configured, list_available_logs, read_log_lines
 
 logger = logging.getLogger(__name__)
 
@@ -56,6 +57,8 @@ def _format_error(e: Exception) -> str:
         return f"Authentication failed: {e}"
     elif isinstance(e, NpmConnectionError):
         return f"Connection error: {e}"
+    elif isinstance(e, NpmLogError):
+        return f"Log error: {e}"
     elif isinstance(e, NpmApiError):
         return f"API error: {e}"
     return f"Error: {e}"
@@ -189,6 +192,14 @@ async def get_system_health() -> str:
         except NpmAuthenticationError:
             result.append("Authenticated: ❌ (check credentials)")
 
+        if is_log_dir_configured():
+            logs = list_available_logs()
+            result.append(f"Log directory: ✅ ({len(logs)} log files found)")
+        else:
+            result.append(
+                "Log directory: ❌ (not configured — set NPM_LOG_DIR to enable get_proxy_host_logs)"
+            )
+
         return "\n".join(result)
 
     except Exception as e:
@@ -448,6 +459,70 @@ async def update_proxy_host(
         return _format_error(e)
 
 
+@mcp.tool()
+async def get_proxy_host_logs(
+    host_id: int,
+    log_type: str = "access",
+    lines: int = 100,
+    search: str | None = None,
+) -> str:
+    """Retrieve recent nginx log entries for a specific proxy host.
+
+    Reads the raw nginx access or error log file for the given host.
+    Requires the NPM log directory to be mounted (see NPM_LOG_DIR config).
+
+    Args:
+        host_id: The ID of the proxy host (use list_proxy_hosts to find IDs)
+        log_type: Log type - "access" for HTTP traffic or "error"
+            for nginx errors (default: "access")
+        lines: Number of most recent lines to return
+            (default: 100, max: 500)
+        search: Optional filter string - only lines containing this
+            text are returned (case-insensitive)
+
+    Returns:
+        The most recent log lines for the proxy host, with metadata.
+
+    Examples:
+        - get_proxy_host_logs(5) — last 100 access log lines for host 5
+        - get_proxy_host_logs(5, log_type="error") — recent error log
+        - get_proxy_host_logs(5, lines=50, search="404") — last 50 lines containing "404"
+        - get_proxy_host_logs(5, search="10.0.0.1") — filter by client IP
+    """
+    try:
+        client = get_client()
+        host = await client.get_proxy_host(host_id)
+        domains = ", ".join(host.domain_names)
+
+        result = read_log_lines(
+            host_id=host_id,
+            log_type=log_type,
+            lines=lines,
+            search=search,
+        )
+
+        header_parts = [
+            f"Proxy host [{host_id}] {domains} — {log_type} log",
+            f"File: {result['file']}",
+        ]
+        if result["total_lines_in_file"] is not None:
+            header_parts.append(f"Total lines in file: {result['total_lines_in_file']}")
+        if result["matched_lines"] is not None:
+            header_parts.append(f"Lines matching '{search}': {result['matched_lines']}")
+        header_parts.append(f"Showing last {result['returned_lines']} lines:")
+
+        header = "\n".join(header_parts)
+
+        if not result["lines"]:
+            return f"{header}\n\n(no log entries found)"
+
+        log_output = "\n".join(result["lines"])
+        return f"{header}\n\n{log_output}"
+
+    except Exception as e:
+        return _format_error(e)
+
+
 @mcp.tool()
 async def create_certificate(
     domain_names: list[str],

tests/test_logs.py

@@ -0,0 +1,146 @@
+"""Tests for the log reader module."""
+
+import pytest
+
+from npm_mcp.exceptions import NpmLogError
+from npm_mcp.logs import (
+    is_log_dir_configured,
+    list_available_logs,
+    read_log_lines,
+)
+
+SAMPLE_ACCESS_LOG = (
+    '[22/May/2025:10:00:01 +0000] - 200 200 - GET https app.example.com'
+    ' "/" [Client 10.0.0.1] [Length 1542] "Mozilla/5.0" "-"\n'
+    '[22/May/2025:10:00:02 +0000] - 301 301 - GET http app.example.com'
+    ' "/old-path" [Client 10.0.0.2] [Length 0] "curl/7.88" "-"\n'
+    '[22/May/2025:10:00:03 +0000] - 404 404 - GET https app.example.com'
+    ' "/missing" [Client 10.0.0.1] [Length 548] "Mozilla/5.0" "-"\n'
+    '[22/May/2025:10:00:04 +0000] - 200 200 - POST https app.example.com'
+    ' "/api/data" [Client 10.0.0.3] [Length 256] "python-requests/2.31" "-"\n'
+    '[22/May/2025:10:00:05 +0000] - 502 502 - GET https app.example.com'
+    ' "/health" [Client 10.0.0.1] [Length 166] "kube-probe/1.28" "-"\n'
+)
+
+SAMPLE_ERROR_LOG = (
+    "2025/05/22 10:00:05 [error] 42#42: *123 connect() failed"
+    " (111: Connection refused) while connecting to upstream,"
+    " client: 10.0.0.1, server: app.example.com\n"
+)
+
+
+@pytest.fixture
+def log_dir(tmp_path, monkeypatch):
+    """Create a temp log directory with sample log files."""
+    logs = tmp_path / "logs"
+    logs.mkdir()
+
+    (logs / "proxy-host-5_access.log").write_text(SAMPLE_ACCESS_LOG)
+    (logs / "proxy-host-5_error.log").write_text(SAMPLE_ERROR_LOG)
+    (logs / "proxy-host-12_access.log").write_text("")
+    (logs / "fallback_error.log").write_text("global error\n")
+
+    monkeypatch.setattr("npm_mcp.logs.settings.log_dir", str(logs))
+    return logs
+
+
+@pytest.fixture
+def no_log_dir(monkeypatch):
+    """Ensure log_dir is unconfigured."""
+    monkeypatch.setattr("npm_mcp.logs.settings.log_dir", "")
+
+
+class TestReadLogLines:
+    def test_read_access_log(self, log_dir):
+        result = read_log_lines(host_id=5, log_type="access")
+        assert result["host_id"] == 5
+        assert result["log_type"] == "access"
+        assert result["file"] == "proxy-host-5_access.log"
+        assert result["returned_lines"] == 5
+        assert result["total_lines_in_file"] == 5
+        assert "app.example.com" in result["lines"][0]
+
+    def test_read_error_log(self, log_dir):
+        result = read_log_lines(host_id=5, log_type="error")
+        assert result["log_type"] == "error"
+        assert result["returned_lines"] == 1
+        assert "Connection refused" in result["lines"][0]
+
+    def test_lines_limit(self, log_dir):
+        result = read_log_lines(host_id=5, log_type="access", lines=2)
+        assert result["returned_lines"] == 2
+        assert "10:00:04" in result["lines"][0]
+        assert "10:00:05" in result["lines"][1]
+
+    def test_lines_capped_at_max(self, log_dir):
+        result = read_log_lines(host_id=5, log_type="access", lines=9999)
+        assert result["returned_lines"] == 5
+
+    def test_search_filter(self, log_dir):
+        result = read_log_lines(host_id=5, log_type="access", search="404")
+        assert result["returned_lines"] == 1
+        assert result["matched_lines"] == 1
+        assert result["total_lines_in_file"] is None
+        assert "/missing" in result["lines"][0]
+
+    def test_search_case_insensitive(self, log_dir):
+        result = read_log_lines(host_id=5, log_type="access", search="MOZILLA")
+        assert result["returned_lines"] == 2
+
+    def test_search_by_ip(self, log_dir):
+        result = read_log_lines(host_id=5, log_type="access", search="10.0.0.1")
+        assert result["returned_lines"] == 3
+
+    def test_nonexistent_host(self, log_dir):
+        with pytest.raises(NpmLogError, match="Log file not found"):
+            read_log_lines(host_id=999, log_type="access")
+
+    def test_empty_log_file(self, log_dir):
+        with pytest.raises(NpmLogError, match="Log file not found"):
+            read_log_lines(host_id=12, log_type="error")
+
+    def test_invalid_log_type(self, log_dir):
+        with pytest.raises(NpmLogError, match="Invalid log type"):
+            read_log_lines(host_id=5, log_type="combined")
+
+    def test_no_log_dir_configured(self, no_log_dir):
+        with pytest.raises(NpmLogError, match="NPM_LOG_DIR is not configured"):
+            read_log_lines(host_id=5, log_type="access")
+
+    def test_nonexistent_log_dir(self, monkeypatch):
+        monkeypatch.setattr("npm_mcp.logs.settings.log_dir", "/nonexistent/path")
+        with pytest.raises(NpmLogError, match="does not exist"):
+            read_log_lines(host_id=5, log_type="access")
+
+
+class TestIsLogDirConfigured:
+    def test_configured(self, log_dir):
+        assert is_log_dir_configured() is True
+
+    def test_not_configured(self, no_log_dir):
+        assert is_log_dir_configured() is False
+
+    def test_configured_but_missing(self, monkeypatch):
+        monkeypatch.setattr("npm_mcp.logs.settings.log_dir", "/nonexistent")
+        assert is_log_dir_configured() is False
+
+
+class TestListAvailableLogs:
+    def test_lists_proxy_host_logs_only(self, log_dir):
+        results = list_available_logs()
+        files = {r["file"] for r in results}
+        assert "proxy-host-5_access.log" in files
+        assert "proxy-host-5_error.log" in files
+        assert "proxy-host-12_access.log" in files
+        assert "fallback_error.log" not in files
+
+    def test_correct_metadata(self, log_dir):
+        results = list_available_logs()
+        access_5 = next(r for r in results if r["file"] == "proxy-host-5_access.log")
+        assert access_5["host_id"] == 5
+        assert access_5["log_type"] == "access"
+        assert access_5["size_bytes"] > 0
+
+    def test_not_configured(self, no_log_dir):
+        with pytest.raises(NpmLogError, match="NPM_LOG_DIR is not configured"):
+            list_available_logs()