claude-code/mods/telemetry

telemetry

Plugin analytics as a plugin: its hooks on telemetry.log and telemetry.mark are what those two events do, built over the nouns its engine.create step is handed, and a gate above them serves the plugins built into Claude Code alone: a call from a plugin a person installed or an administrator listed is refused with a reason (the host stamps every call with the plugin that raised it, next.origin, and the gate reads its tier). On an engine that has no $.telemetry of its own the same step adds the noun, so the calls exist there too. An entry names where it goes with to: anthropic, the default, is this mod's; one for collector, the telemetry collector an operator configured, is passed on beneath untouched, and to is never part of a row. $.telemetry.log({ event, props }) queues one event as one first-party row, tengu_plugin_<event>; $.telemetry.mark({ feature, kind, reason?, props? }) marks one use of a feature as the CLI's own feature events do, tengu_feature_<kind> with a feature_name and the mark's properties beside it. Both resolve once the row is queued. Rows go out in batches: one POST to the event-logging ingest with the session's own credential ($.session.authorize(), resolved for each batch) a few seconds after the first row was queued, at once when a hundred wait, and when the session ends; a batch the ingest refuses with a server error, a timeout or a rate limit is tried once more. A session with no first-party credential, or an ingest that still refuses, drops the batch; each outcome is one line in the debug log.

Each row carries what the CLI's own rows carry, gathered through $ once a session: an event id, the install's device id and the signed-in account's ids from the CLI's global config, the session's id, model, client type, entrypoint and interactivity, and an env block (platform and architecture from one uname probe, terminal, shell, package managers and runtimes, CI and GitHub Actions, the remote container, the deployment, the Linux distribution and kernel, WSL, the working directory's version control, and the engine's version, base version and build time from $.session.version(), left empty on an engine that does not answer it), with the repository's remote hash beside the row's properties. What the engine alone knows (its runtime's version, the process's memory, the request's betas, the subscription tier, the calling agent) is not on $, and those columns stay empty.

It sends nothing wherever the CLI's own analytics are off: under DISABLE_TELEMETRY, CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC or DO_NOT_TRACK, in a test run, on any third-party provider (Bedrock, Vertex, Foundry and kin) the host does not manage, on a cloud gateway (the environment's switch or the managed policy's login pins), and on a deployment with its own OAuth URL. Each is read through $.env and $.settings before every batch, so a session that has since moved to a third-party provider or a gateway sends nothing more; when the switches cannot be read, nothing is sent either. The row's user_type is ant when USER_TYPE says so, else external.

Nothing free-form reaches a row. An event name and every property key is a snake_case token; a value is a finite number, a boolean, or a Choice (a string named together with the list it is chosen from), under log and mark alike; mark takes ok, sad or bad, with a reason required on the last two and refused on the first. An entry that breaks a rule is refused before anything is queued. Of the environment, a variable whose value is a secret, or names a person or a host, is read for whether it is set and nothing more; a shell is its basename from a closed list.

hooks/register.ts is the module; types/index.d.ts is the noun's contract, the one declaration of $.telemetry that this mod's hooks, a mod calling the noun and a test answering it all read.

What it hooks

telemetry.*, the gate: a caller in the built-in tier (or the engine) goes on, any other is refused, and a gate that throws refuses too. telemetry.log and telemetry.mark, beneath the gate: the entry is checked and its row queued, the hook answering { value }, or { deny } with the reason for an entry that breaks a rule, so the caller's promise rejects naming it. engine.create: the sender is built over await next(e), and the step hands up { ...{ telemetry }, ...beneath }: what is beneath is spread last, so its own telemetry stands where it has one and this mod's is added where it has none; nothing beneath is replaced. session.start, to learn whether a person is at the prompt; session.end, to send what still waits.

What it calls on $

session.authorize, session.id, session.model, session.surfaces, session.cwd, session.repo, settings.read, env.get (the switches and the describing variables, by literal name), fs.read, fs.list, fs.exists, process.run (one sh -c of uname and command -v), clock.after, clock.sleep, http.fetch and ui.log (to the debug log), each on the interface the fold handed it.

Where it runs, whom it serves

This plugin is seated by the CLI itself, on every build whose own analytics are on, and nowhere else; it serves the plugins bundled with the CLI and refuses every other caller. It is not meant to be installed or loaded with --plugin-dir; the folder has a manifest so it reads like every other plugin, not so it can stand alone. A built-in that calls $.telemetry where this one is absent finds no such noun, or, on an engine with the noun of its own, one whose calls queue nothing; either way that is "no analytics here".