@gcornut/opencode-otel

OpenTelemetry metrics and structured log events plugin for OpenCode. Mirrors the telemetry surface of Claude Code so you can reuse the same OTEL collector and dashboards.

Install

Add to your opencode.json:

{
  "plugin": ["@gcornut/opencode-otel"]
}

Or as a local plugin, copy the src/ directory to .opencode/plugins/otel/.

Configuration

Create ~/.config/opencode/otel.json:

{
  "endpoint": "https://<endpoint>",
  "protocol": "grpc",
  "metricsExporter": "otlp",
  "logsExporter": "otlp",
  "headers": {
    "Authorization": "Bearer <token>"
  },
  "resourceAttributes": {
    "user.email": "[email protected]",
    "department": "engineering"
  },
  "logUserPrompts": false,
  "logToolDetails": false,
  "includeSessionId": true,
  "includeVersion": false,
  "includeAccountUuid": true,
  "metricExportIntervalMs": 60000,
  "logsExportIntervalMs": 5000,
  "metricsTemporality": "delta"
}

All fields are optional except endpoint — without it, telemetry is disabled. Only set what you need.

You can override the config file path with OPENCODE_OTEL_CONFIG_PATH=/path/to/otel.json.

Config reference

| Field | Type | Default | Description | |---|---|---|---| | endpoint | string | (required) | Collector URL (e.g. https://otel.example.com) | | metricsEndpoint | string | | Override endpoint for metrics only | | logsEndpoint | string | | Override endpoint for logs only | | metricsExporter | string | "otlp" | "otlp", "console", or "none" | | logsExporter | string | "otlp" | "otlp", "console", or "none" | | protocol | string | "grpc" | "grpc", "http/json", or "http/protobuf" | | headers | object | {} | HTTP headers for OTLP requests | | resourceAttributes | object | {} | Key-value pairs added to all telemetry | | metricExportIntervalMs | number | 60000 | Metrics export interval (ms) | | logsExportIntervalMs | number | 5000 | Logs export interval (ms) | | metricsTemporality | string | "delta" | "delta" or "cumulative" | | logUserPrompts | boolean | false | Include prompt text in log events | | logToolDetails | boolean | false | Include tool names and args in log events | | includeSessionId | boolean | true | Include session.id on metrics and events | | includeVersion | boolean | false | Include app.version on metrics and events | | includeAccountUuid | boolean | true | Include user.account_uuid on metrics | | telemetryProfile | string | "opencode" | "opencode" or "claude-code" — emit events using Claude Code's naming | | onlyForProvider | string | string[] | | When set, only emit telemetry for this provider ID(s). Single provider ID as string, or array of provider IDs |

Telemetry profile

When set to "claude-code", the plugin emits telemetry that closely matches Claude Code's built-in telemetry: same service.name (claude-code), same meter name (com.anthropic.claude_code), same logger name (com.anthropic.claude_code.events), same metric names (claude_code.*), and same event body format (claude_code.*). This lets you reuse Claude Code dashboards and alerting rules without modification.

Example: minimal config

{
  "endpoint": "https://otel-collector.example.com"
}

Example: with per-signal endpoints

{
  "endpoint": "https://otel-collector.example.com",
  "metricsEndpoint": "https://metrics.example.com/v1/metrics",
  "logsEndpoint": "https://logs.example.com/v1/logs"
}

Disabling telemetry

To disable telemetry without removing the plugin, set both exporters to "none":

{
  "endpoint": "https://otel-collector.example.com",
  "metricsExporter": "none",
  "logsExporter": "none"
}

Example: filter by provider

To only emit telemetry when using a specific model provider (e.g., only for Vertex AI with Claude):

{
  "endpoint": "https://otel-collector.example.com",
  "onlyForProvider": "google-vertex-anthropic"
}

To emit telemetry for multiple providers, use an array:

{
  "endpoint": "https://otel-collector.example.com",
  "onlyForProvider": ["google-vertex-anthropic", "google-vertex"]
}

When onlyForProvider is set, telemetry filtering works as follows:

1. Before first chat.message: Provider-specific events are buffered until the provider is known
2. After provider detected:
   • Provider matches → buffered events are flushed and subsequent events are emitted
   • Provider doesn't match → buffered events are discarded and subsequent events are skipped
3. Provider switching: If the user changes to a different provider mid-session, telemetry automatically toggles on/off based on the new provider

Provider-agnostic metrics (always emitted regardless of provider):

• Session count, active time, lines of code, tool decisions, commits, pull requests

Provider-specific telemetry (filtered by provider):

• Token usage, cost, API requests, tool results, user prompts, error events

Common provider IDs: google-vertex-anthropic, google-vertex, opencode, anthropic.

Telemetry signals

8 metrics (counters): session.count, active_time.total, token.usage, cost.usage, lines_of_code.count, commit.count, pull_request.count, tool.decision

3 events (OTEL Log records): user_prompt, tool_result, api_request

All signals include user.id, session.id, and terminal.type attributes. Events also include event.timestamp (ISO 8601), event.sequence, and prompt.id.

With telemetryProfile: "claude-code", metric names use the claude_code.* prefix and the wire format closely matches Claude Code's built-in telemetry. See docs/claude-code-vs-opencode-otel.md for a detailed comparison.

Development

bun install
bun run typecheck
bun run build
bun test

Local testing with collector

# Start the built-in OTLP collector
bun run otel:collect -o telemetry.jsonl

# In another terminal, run opencode or claude with telemetry pointed at localhost:4318
# Then compare captures:
bun run otel:compare claude.jsonl opencode.jsonl

License

MIT