agentmetrics-anthropic (JS/TS)

AgentMetrics integration for Claude Managed Agents (JavaScript/TypeScript). Wrap your session event stream with one tracker and every session reports back to your dashboard when it terminates showing latency, cost, token counts with cache, tool calls, and errors.

Install

npm install agentmetrics-anthropic

Quickstart

import Anthropic from "@anthropic-ai/sdk";
import { AgentMetricsSessionTracker } from "agentmetrics-anthropic";

const client  = new Anthropic();
const tracker = new AgentMetricsSessionTracker({
  agentId: "my-claude-agent",
  baseUrl: "http://localhost:8099",
});

// Wrap an existing stream
const rawStream = client.beta.sessions.events.stream("sess_...");
const tracked   = tracker.wrap(rawStream, "sess_...");

for await (const event of tracked) {
  // handle events as normal
}

Higher-level helper

await tracker.track(client, "sess_...", async (stream) => {
  for await (const event of stream) {
    // handle events
  }
});

API

new AgentMetricsSessionTracker(opts)

| Option | Default | Description | |---|---|---| | agentId | "anthropic-agent" | Label shown in the dashboard | | baseUrl | "http://localhost:8099" | AgentMetrics server address |

.wrap(rawStream, sessionId)

Returns a new async iterable that passes all events through unchanged. Emits a run summary when session.status_terminated is received or the iterator exhausts.

.track(client, sessionId, fn, ...streamArgs)

Opens a session event stream, wraps it with tracking, and passes the tracked stream to fn. Emits metrics on completion or error.

What gets tracked

Each session emits one event to /v1/events when it terminates:

| Field | Description | |---|---| | status | success or failed | | duration_ms | Wall-clock session duration | | input_tokens / output_tokens | Aggregated across all LLM calls | | cache_read_tokens / cache_write_tokens | Cache token counts | | llm_calls | Number of LLM requests in the session | | tool_calls / tool_errors | Tool usage counts | | tool_names | Array of tools invoked | | model | Model name from the first LLM call | | estimated_cost_usd | Computed from token counts and model pricing | | error | First 500 chars of the error message on failure |

License

MIT