MCP server

Lumin serves a remote MCP server at https://api.getlumin.dev/v1/mcp. A coding agent connects to it with a read-only API key and can then read one project’s telemetry with ten tools. Nothing runs on your machine, and the server never writes.

Connect in one minute

1. Open Settings → API keys → New key in the project you want the agent to read.
2. Pick the kind Coding agent (read-only). The key starts with lmn_read_.
3. Copy the snippet for your client from the key dialog, or use one of these:

Claude Code

claude mcp add --transport http lumin https://api.getlumin.dev/v1/mcp \
  --header "Authorization: Bearer lmn_read_..."

Cursor (~/.cursor/mcp.json or .cursor/mcp.json)

{
  "mcpServers": {
    "lumin": {
      "url": "https://api.getlumin.dev/v1/mcp",
      "headers": { "Authorization": "Bearer ${env:LUMIN_READ_KEY}" }
    }
  }
}

VS Code (.vscode/mcp.json)

{
  "inputs": [
    { "type": "promptString", "id": "lumin-key", "description": "Lumin read-only API key", "password": true }
  ],
  "servers": {
    "lumin": {
      "type": "http",
      "url": "https://api.getlumin.dev/v1/mcp",
      "headers": { "Authorization": "Bearer ${input:lumin-key}" }
    }
  }
}

Codex CLI (~/.codex/config.toml)

[mcp_servers.lumin]
url = "https://api.getlumin.dev/v1/mcp"
bearer_token_env_var = "LUMIN_READ_KEY"

Windsurf, Gemini CLI, Zed, JetBrains AI Assistant, and OpenCode accept the same URL with the same Authorization header. claude.ai connectors and ChatGPT need OAuth, which Lumin does not offer yet.

Then ask the agent a question about production. Three to try:

• “What errored in the last hour, and which service?”
• “Is any uptime check down? Since when?”
• “The checkout endpoint got slow after this morning’s deploy. What happened?”

Claude Code also gets the /mcp__lumin__investigate prompt, which walks the tools in the order that finds a cause fastest.

The tools

Every tool reads the project bound to the key. No tool takes a project argument, and no tool writes.

Tool	What it returns
get_project_overview	The project, its environments, the services seen in the last hour, service health, the 24 h check summary, alert rules and open incidents, and host and container counts. Call it first.
search_logs	One page of log rows, newest first, filtered by window, level, service, query text, or trace id. Default 50 rows, max 200, window up to 30 days.
get_log_context	The rows written right before and after one row id.
get_log_volume	Rows per level over time, plus the loudest services. Use it to find when a problem started.
list_metrics	Metric names and kinds emitted in the last 30 days.
query_metric	One metric aggregated into time series, with group_by, label filters, and a min, max, avg, last summary per series. At most 20 series and 300 points per series.
get_checks	Uptime checks with status, uptime percentage, latest latency, and the periods each check was down. Window up to 90 days.
get_alerts	Alert rules with their condition as text, and incidents with open ones first.
get_infrastructure	The latest host and container metrics from lumin-agent.
search_events	Browser and mobile SDK events, errors by default, or page views, tracked actions, and identify calls.

Time arguments accept a relative age (15m, 2h, 7d), the word now, an RFC3339 time, or unix seconds or milliseconds. Every tool takes an optional environment argument. The default is the environment bound to the key. Pass all to span every environment.

Log search uses the same grammar as the Logs page: bare words match the message and combine with AND, -word excludes, "quoted phrase" matches exactly, level:error, service:api, and trace_id:abc filter columns, and attr.key:value matches a JSON attribute.

Limits

• The key reads one project. Mint one key per project you want the agent to see.
• 120 calls per minute per key. The server answers 429 with a Retry-After header above that.
• Four tool calls run at the same time per instance. A fifth waits up to five seconds and then returns a tool error.
• Results are capped: log messages at 2 KiB, attributes at 2 KiB, error stacks at 4 KiB. A clipped row carries truncated: true.

Security

• Read-only. The server exposes no write tool, and the ten tools are annotated readOnlyHint so clients can show them as safe. A lmn_read_ key is refused by every ingest endpoint, and an ingest key is refused by the MCP server.
• Project-scoped. The project comes from the key, never from an argument. A key cannot name another project.
• Revoke to cut access. Revocation takes effect on the next call. Rotate a key that landed in a shared config or in shell history.
• Log content is data, not instructions. Log lines, attributes, event properties, and label values are written by your services and by whoever talks to them. Every result that carries such text says so in a notice field, and control characters are stripped. Your agent’s own guardrails decide what it does with that text. Read the agent security model for the same rule on the ingest side.
• Instance kill switch. The operator can turn the server off for the whole instance. It then answers 403 on every call.

Server card

The server publishes a card for agents that discover MCP servers by domain. Upstream has not settled on one path, so the card answers at all three that clients probe:

Path	Origin
/v1/mcp/server-card	Next to the streamable endpoint
/.well-known/mcp/server-card.json	SEP-2127
/.well-known/mcp.json	SEP-1649, still probed

Every path returns the same document, with Access-Control-Allow-Origin: * so a browser client can read it. api.getlumin.dev and getlumin.dev both serve it.