Tracer

@open-agent-loops/core

Defined in: observability/tracer.ts:94

Accessors

durationMs

Get Signature

get durationMs(): number;

Defined in: observability/tracer.ts:246

Total wall-clock span of the trace (ms), or 0 if empty.

Returns

number

startedAt

Get Signature

get startedAt(): number | undefined;

Defined in: observability/tracer.ts:252

Epoch ms of the first recorded entry — the base for every entry's dt.

Returns

number | undefined

Constructors

Constructor

new Tracer(options?): Tracer;

Defined in: observability/tracer.ts:110

Parameters

Returns

Tracer

Methods

clear()

clear(): void;

Defined in: observability/tracer.ts:257

Drop all recorded entries and metadata, and reset the clock origin.

Returns

void

curls()

curls(options?): string[];

Defined in: observability/tracer.ts:476

Every captured request rendered as a runnable curl, in turn order — paste any to replay that exact call. Maps requests() through toCurl, defaulting baseURL from meta.baseURL (seeded by onRequest) so the call site doesn't stitch the endpoint together. Pass baseURL to override; the rest of ToCurlOptions (apiKeyEnv, stream, pretty, path) pass straight through.

Parameters

Returns

string[]

Throws

if no baseURL is known — wire onRequest, or pass options.baseURL.

disclosure()

disclosure(): DisclosureStep[];

Defined in: observability/tracer.ts:409

The progressive-disclosure timeline: one step per captured request, each diffed against the previous to show tools added/removed and how the context window grew. Requires observe() (the only seam that sees the request).

Returns

DisclosureStep[]

flush()

flush(): Promise<void>;

Defined in: observability/tracer.ts:124

Flush the async write queue and await the sink. Call once at run end so the tail isn't lost (no-op when only the synchronous log is used).

Returns

Promise<void>

format()

format(options?): string;

Defined in: observability/tracer.ts:341

Full timeline, one entry per line: [+12ms] agent tool_end weather ok → "...".

Parameters

Returns

string

formatDisclosure()

formatDisclosure(options?): string;

Defined in: observability/tracer.ts:436

Compact view of how disclosure evolved: tools ± and context size per turn.

Parameters

Returns

string

formatTrajectory()

formatTrajectory(options?): string;

Defined in: observability/tracer.ts:373

Compact per-turn view: the action and its observations, with timings.

Parameters

Returns

string

observe()

observe(model): ModelClient;

Defined in: observability/tracer.ts:190

Wrap a ModelClient so its StreamEvents are captured (finer grain) and the system prompt + tool names are pulled from each request into meta.

Parameters

Returns

ModelClient

onRawRequest()

readonly onRawRequest(body): void;

Defined in: observability/tracer.ts:169

Tap for OpenAICompatibleModel({ onRawRequest }): captures the full assembled request body off the wire — the exact JSON POSTed to the model, with the complete tool-call history. One entry per model turn. Together with meta.baseURL (from onRequest) these reconstruct a reproducible curl.

Parameters

Returns

void

onRawSSE()

readonly onRawSSE(line): void;

Defined in: observability/tracer.ts:159

Tap for OpenAICompatibleModel({ onRawSSE }): captures raw response-wire lines (fire-and-forget).

Parameters

Returns

void

onRequest()

readonly onRequest(info): void;

Defined in: observability/tracer.ts:177

Tap for OpenAICompatibleModel({ onRequest }): records the model id, base URL, sampling params, and system prompt into meta.

Parameters

Returns

void

requests()

requests(): unknown[];

Defined in: observability/tracer.ts:460

The request body POSTed each model turn, in turn order — the exact JSON the provider sent, with the growing tool-call history. The structured accessor for the request wire (the request_body entries from onRawRequest): it owns the label filter and unwraps the RawRequest payload, so callers don't reach into entries/data. Pair to curls() like trajectory() / formatTrajectory(). Empty unless onRawRequest is wired.

Returns

unknown[]

setMeta()

setMeta(partial): void;

Defined in: observability/tracer.ts:132

Merge run metadata, ignoring undefined fields so partial taps don't clear what's already known.

Parameters

Returns

void

toJSON()

toJSON(): TraceDocument;

Defined in: observability/tracer.ts:265

The whole trace as one JSON document: run config + compact timeline.

Returns

TraceDocument

toJSONL()

toJSONL(): string;

Defined in: observability/tracer.ts:485

One compact JSON object per line — machine-readable, append-friendly.

Returns

string

trajectory()

trajectory(): TrajectoryStep[];

Defined in: observability/tracer.ts:279

Fold the agent events into one (action -> observations) pair per model turn. assistant is the action; tools are the observations it produced. Built only from "agent" entries, so it works whether or not SSE/model capture is on.

Returns

TrajectoryStep[]

Properties