Spanlens SDK for Python. Agent tracing, LLM usage capture, and cost observability.
Spanlens SDK for Python. Agent tracing, LLM usage capture, and cost observability. That is what the spanlens mcp server brings to an AI assistant: the same capability, reachable through the Model Context Protocol rather than a separate app or dashboard.
@spanlens/sdk with your package manager (npm / pnpm / yarn / bun) 2. Writes SPANLENS_API_KEY to .env.local 3. Rewrites every new OpenAI({ apiKey, baseURL }) into createOpenAI()Configuration is passed through the environment: SPANLENS_API_KEY, RESEND_API_KEY, NEXT_PUBLIC_SUPABASE_URL, NEXT_PUBLIC_SUPABASE_ANON_KEY, SUPABASE_URL, SUPABASE_ANON_KEY, SUPABASE_SERVICE_ROLE_KEY, ENCRYPTION_KEY. Treat anything key-shaped as a real credential — scope it to the minimum the server needs, and rotate it if it ever lands in a shared config.
Because this one is hosted, setup is mostly authentication — you point your client at the endpoint and approve access. Nothing runs on your machine, so there is no runtime to keep patched.
Among the monitoring and observability options, the useful question is rarely "what can it do" but "what does it cost you to run" — permissions, credentials, and how much of your context its toolset consumes.
This entry was verified against Spanlens's own documentation before publication; SyncDev keeps the directory reviewed rather than auto-generated.
{
"mcpServers": {
"spanlens": {
"command": "npx",
"args": ["-y", "@spanlens/cli"],
"env": {
"SPANLENS_API_KEY": "your-value",
"RESEND_API_KEY": "your-value",
"NEXT_PUBLIC_SUPABASE_URL": "your-value",
"NEXT_PUBLIC_SUPABASE_ANON_KEY": "your-value",
"SUPABASE_URL": "your-value",
"SUPABASE_ANON_KEY": "your-value",
"SUPABASE_SERVICE_ROLE_KEY": "your-value",
"ENCRYPTION_KEY": "your-value"
}
}
}
}Add to claude_desktop_config.json, then restart Claude Desktop.
| Variable | Description | Required |
|---|---|---|
| SPANLENS_API_KEY | Credential the server authenticates with. | Yes |
| RESEND_API_KEY | Credential the server authenticates with. | Yes |
| NEXT_PUBLIC_SUPABASE_URL | Endpoint or connection string the server talks to. | Yes |
| NEXT_PUBLIC_SUPABASE_ANON_KEY | Credential the server authenticates with. | Yes |
| SUPABASE_URL | Endpoint or connection string the server talks to. | Yes |
| SUPABASE_ANON_KEY | Credential the server authenticates with. | Yes |
| SUPABASE_SERVICE_ROLE_KEY | Credential the server authenticates with. | Yes |
| ENCRYPTION_KEY | Credential the server authenticates with. | Yes |
Give your coding agent the full DevTools toolbox: traces, network, console, heap snapshots and Lighthouse.
Dashboards, Prometheus and Loki queries, incidents and alerts — observability by conversation.
Errors with full context — stack traces, issue triage and AI-powered root-cause analysis from Sentry's server.
Enables enhanced web research capabilities for large language models through intelligent search queuing and advanced content extraction.
Automates browser interactions and enables Large Language Models (LLMs) to interact with web pages through Playwright and Chrome DevTools Protocol
Guides tool usage by providing recommendations for MCP tools at each problem-solving stage.