Tracking Plan Audit

Tracking Plan Audit

Produce a deletion-focused, evidence-backed cleanup inventory. This skill specializes in deletion audits across telemetry, source code, ownership, dependencies, and tracking-plan branches. Use taxonomy for broad taxonomy design, naming, metadata, and governance guidance.

Do not add or restore taxonomy objects, make metadata-only changes, or create, mutate, merge, or delete an Amplitude branch unless the user explicitly asks.

At the start, establish:

• the Amplitude project and environment;
• whether the goal is lower ingestion volume, fewer taxonomy types, or both;
• every repository or directory that may emit the project's data;
• the requested audit mode and lookback window.

Source-code gate

Source code is required. If the user has not identified every repository or directory that can emit into the project, ask for those locations before recommending deletion candidates. You may inventory taxonomy objects while waiting, but label the result incomplete and do not recommend or execute any deletion. Before lifting this gate, ask the user to confirm that the supplied source inventory covers every known emitter. Never report "no code reference" unless every user-identified source root was searched.

Do not assume repository names, services, languages, project IDs, event names, observability systems, or filesystem layouts. Inspect each source root's local instructions before searching it.

Route the audit

Choose a primary mode and state it before discovery. Run additional requested modes sequentially so each keeps its own criteria. Read references/modes.md for each mode's criteria.

1. General stale events/properties
2. Cross-app overlap
3. Planned but never ingested
4. Global orphan properties
5. Dead generated-client definitions
6. Duplicate events/properties
7. Retired features, routes, flags, or experiments
8. High-volume, low-query instrumentation
9. Code still emitting deleted or blocked events

If the user requests taxonomy changes, also read references/mutations.md before any mutation.

Non-negotiable evidence rules

• Keep telemetry, query/dependency usage, code references, source ownership, and taxonomy state as separate signals. No single signal proves deletion is safe.
• Audit every identified source root. Include generated clients, direct SDK use, wrappers, dynamic dispatch, frontend, backend, mobile, jobs, and integrations where present.
• A generated definition is potential usage, not a production call site. Trace its method or class through imports, wrappers, registries, aliases, tests, and production callers.
• A literal-search miss is insufficient. Check generic trackers, constructed names or keys, dictionary spreads, serializers, constants, and service-specific clients.
• Determine whether each enclosing code path is reachable through imports, route wiring, flags, experiments, jobs, tests, and callers. Distinguish dead code from a live feature whose analytics call alone should be removed.
• Recent ingestion with no owner in the known roots indicates an external or unidentified source. Report it and ask for another likely source root before recommending deletion.
• Check charts, dashboards, cohorts, metrics, experiments, transformations, derived properties, lookups, alerts, exports, and other relationships where available. A zero saved-query count does not prove there is no dependency. If a required dependency surface is unavailable, mark it unresolved and do not recommend deletion.
• When retirement or production activity matters, ask which monitoring, feature-flag, experimentation, and deployment systems the user has connected. Prefer their read-only MCP or app capabilities over assumptions or manual screenshots.
• Treat default/system objects and experiment, session-replay, or agent fields cautiously unless the selected mode explicitly investigates them.
• Do not expose credentials, property values, PII, customer payloads, or other customer-sensitive data. Report aggregates, names only when necessary, and access-controlled evidence links.

Public Amplitude MCP capabilities

Inspect the connected public Amplitude MCP catalog at runtime and use only the capabilities, action values, parameters, and limits it advertises. Do not hard-code or invent tool names: public tools can be consolidated, renamed, or exposed differently during a rollout.

Use the available capabilities to:

• discover accessible projects and ask the user to select one when its ID is missing; never infer an ID from a name;
• read raw events and event properties, preferring the consolidated taxonomy reader when the catalog exposes one;
• include deleted objects when comparing states or historical ownership;
• select exactly one branch identifier when auditing a tracking-plan branch;
• distinguish project-wide/global properties from properties attached to one event using the response's documented scope fields.

For mutation capability selection and exact confirmation behavior, read references/mutations.md.

Complete taxonomy reads

For every exhaustive paginated read:

1. Request the largest supported page size, up to 500.
2. Follow every returned cursor until the response says there are no more rows.
3. Track unique rows using the response's stable identity plus property/event scope, then compare the accumulated count with the API's reported total.
4. Retry transient timeouts and gateway/server failures from the last known cursor using bounded retries and backoff appropriate to the connected host. Never treat an error payload or failed empty page as completion.
5. If retries are exhausted or counts disagree, report incomplete coverage and do not recommend deletions from the partial result.

Use a complete tracking-plan export when available to reconstruct event-to-property ownership and compare main with a branch. A project-wide property listing exposes global definitions but may not enumerate every event attachment. Do not infer ownership from it alone, the export Action column, or branch UI counters; compare taxonomy states explicitly.

Shared audit workflow

1. Snapshot the relevant main or branch taxonomy and telemetry window.
2. Fully paginate required reads and record coverage against reported totals.
3. Build ownership from complete exports, including active and deleted scopes.
4. Search every identified source root; classify production, dynamic, generated-only, test-only, dead, and unknown-external references.
5. Check dependencies and resolve every code, ownership, and source signal.
6. Classify candidates by confidence, evidence, uncertainty, and recommended deletion transition.
7. After any event deletion, always perform a global orphan-property sweep. Present global property candidates separately and ask for separate explicit confirmation; event deletion never authorizes or implies global deletion.

Strong candidates normally have no reachable emitter, no recent ingestion, little or no query usage, no active owner or dependency, and no unresolved dynamic or external source. Existing telemetry, dependencies, generic names, required schemas, or unknown ownership require investigation, not deletion.

For properties, report at least:

property | scope/owners | code references by source | volume/query window | last seen | required | dependencies | confidence | recommendation

Also report source coverage, exclusions, unresolved paths, sensitive-data redactions, and a reviewable batch. Keep mutation batches within the user's requested limit; otherwise prefer a small first batch.