Setup Install Braintrust alongside the Pi Coding Agent SDK, then set your API keys. Requires `@earendil-works/pi-coding-agent` v0.79.x. ```bash pnpm theme={"theme":{"light":"github-light","dark":"github-dark-dimmed"}} pnpm add braintrust @earendil-works/pi-coding-agent ``` ```bash npm theme={"theme":{"light":"github-light","dark":"github-dark-dimmed"}} npm install braintrust @earendil-works/pi-coding-agent ``` ```bash title=".env" theme={"theme":{"light":"github-light","dark":"github-dark-dimmed"}} BRAINTRUST_API_KEY= ANTHROPIC_API_KEY= ``` Auto-instrumentation To trace Pi Coding Agent SDK runs without wrapping the SDK module yourself, initialize Braintrust normally, then run your app with Braintrust’s import hook to patch the SDK at runtime. ```javascript title="trace-pi-coding-agent-auto.js" theme={"theme":{"light":"github-light","dark":"github-dark-dimmed"}} import { initLogger } from "braintrust"; import { AuthStorage, ModelRegistry, SessionManager, createAgentSession, } from "@earendil-works/pi-coding-agent"; initLogger({ projectName: "pi-coding-agent-example", // Replace with your project name apiKey: process.env.BRAINTRUST_API_KEY, }); const authStorage = AuthStorage.inMemory(); authStorage.setRuntimeApiKey("anthropic", process.env.ANTHROPIC_API_KEY ?? ""); const modelRegistry = ModelRegistry.inMemory(authStorage); modelRegistry.registerProvider("anthropic", { baseUrl: process.env.ANTHROPIC_BASE_URL, }); const model = modelRegistry.find("anthropic", "claude-sonnet-4-5"); if (!model) { throw new Error("Pi Coding Agent model not found"); } const { session } = await createAgentSession({ authStorage, cwd: process.cwd(), model, modelRegistry, sessionManager: SessionManager.inMemory(process.cwd()), thinkingLevel: "off", tools: ["bash"], }); await session.prompt("Run `pwd` and summarize the result.", { expandPromptTemplates: false, }); session.dispose?.(); ``` ```bash theme={"theme":{"light":"github-light","dark":"github-dark-dimmed"}} node --import braintrust/hook.mjs trace-pi-coding-agent-auto.js ``` The auto-instrumentation example uses plain JavaScript so `node --import` can run the file directly. The Braintrust APIs work the same in TypeScript projects — compile your TypeScript to JavaScript, then run the compiled file with the import hook. If you’re using a bundler, see [Trace LLM calls](/instrument/trace-llm-calls#auto-instrumentation) for plugin and loader setup. If you manage instrumentation hooks directly with `@braintrust/auto-instrumentations`, keep the Pi Coding Agent integration enabled. Manual instrumentation To trace the Pi Coding Agent SDK manually, wrap the imported module yourself with `wrapPiCodingAgentSDK()` before creating sessions. ```javascript JavaScript theme={"theme":{"light":"github-light","dark":"github-dark-dimmed"}} import { initLogger, wrapPiCodingAgentSDK } from "braintrust"; import * as pi from "@earendil-works/pi-coding-agent"; initLogger({ projectName: "pi-coding-agent-example", // Replace with your project name apiKey: process.env.BRAINTRUST_API_KEY, }); const { AuthStorage, ModelRegistry, SessionManager, createAgentSession, } = wrapPiCodingAgentSDK(pi); const authStorage = AuthStorage.inMemory(); authStorage.setRuntimeApiKey("anthropic", process.env.ANTHROPIC_API_KEY ?? ""); const modelRegistry = ModelRegistry.inMemory(authStorage); modelRegistry.registerProvider("anthropic", { baseUrl: process.env.ANTHROPIC_BASE_URL, }); const model = modelRegistry.find("anthropic", "claude-sonnet-4-5"); if (!model) { throw new Error("Pi Coding Agent model not found"); } const { session } = await createAgentSession({ authStorage, cwd: process.cwd(), model, modelRegistry, sessionManager: SessionManager.inMemory(process.cwd()), thinkingLevel: "off", tools: ["bash"], }); await session.prompt("Run `pwd` and summarize the result.", { expandPromptTemplates: false, }); session.dispose?.(); ``` What Braintrust traces Braintrust patches `AgentSession.prompt()` and captures: * Task spans for each `AgentSession.prompt()` call. * Anthropic LLM spans nested under the prompt span, including model metadata, stop reasons, and token metrics. * Tool spans for tool invocations, including `bash` calls, tool names, inputs, outputs, and tool call IDs. * Pi Coding Agent metadata under keys such as `pi_coding_agent.operation`, `pi_coding_agent.api`, `pi_coding_agent.model`, `pi_coding_agent.source`, `pi_coding_agent.stop_reason`, and `pi_coding_agent.tool.name`. * OpenTelemetry GenAI tool metadata, including `gen_ai.tool.name` and `gen_ai.tool.call.id`. * Errors captured on task, LLM, and tool spans. Resources * [Pi Coding Agent SDK on npm](https://www.npmjs.com/package/@earendil-works/pi-coding-agent) * [pi documentation](https://pi.dev)