Cleanup Feature Flags

Remove one launched FME flag from application code and keep the branch FME serves today. The work ends with a PR. FME is read-only here; archive happens later in manage-flag-lifecycle.

Related: discover-feature-flags finds candidates (stale audit); manage-flag-lifecycle archives after the change deploys.

Tools

Works through the Harness MCP server or the Harness CLI; names are from tool-map.md.

Operation	MCP	CLI
List environments	harness_list · fme_environment · compact: false	harness list fme_environment --json
Get flag	harness_get · fme_feature_flag · params: { feature_flag_name }	harness get feature_flag <flag> --json
List flag definitions	harness_list · fme_feature_flag_definition · params: { feature_flag_name } · filters: { offset: 0, limit: 100 } · compact: false	harness list feature_flag:definition <flag> --json
List experiments	harness_list · fme_experiment · filters: { parent_type: "FEATURE_FLAG", parent_name, status: ["ACTIVE", "PAUSED"], offset: 0, limit: 100 } (apply pagination completeness checks) · compact: false	harness list experiment --parent-type FEATURE_FLAG --parent-name <flag> --status ACTIVE --json, then again with --status PAUSED

Instructions

Load readiness.md before giving a verdict. Load sdk-patterns.md before searching code.

Phase 1: Establish scope

Follow scope-establishment.md. Fully paginate List environments per pagination before confirming the critical environments: by default those with isProduction, plus any the user adds. The critical set must be non-empty and explicitly confirmed back to the user before any later phase. If no environment is marked isProduction and the user hasn't named any, STOP and ask which environments are critical — do not treat an empty critical set as vacuously ready.

Phase 2: Pick the flag

If the user named a flag, Get flag to confirm it exists and note its status and rolloutStatus. If they want candidates instead, hand off to discover-feature-flags (stale audit) and come back with one flag.

Phase 3: Forward treatment and verdict

1. Fully paginate List flag definitions for the flag with explicit MCP filters.limit: 100 and advancing filters.offset until a short page (size is ignored). Incomplete coverage stops code removal; it cannot establish a missing definition or the live forward treatment. Resolve the forward treatment for each critical environment per readiness.md. If any call site uses WithConfig, also resolve and compare each critical environment's configurations value for that treatment — identical treatment names with differing configs are blocked, not ready.
2. Run the experiment check with List experiments, covering every page of ACTIVE and PAUSED results before a verdict. An incomplete scan stops code removal. Here ACTIVE means blocked: code removal ends the experiment. PAUSED means caution.
3. Give the verdict per readiness.md. Stop on blocked.

Never infer the forward treatment from the code's default or fallback value.

Phase 4: Find call sites

In the application repo, identify the SDK and search for the flag key, batch calls, flag sets, config-file entries and tests per sdk-patterns.md. For each hit, record file:line, which branch is the forward one, and any side effects (tracking, metrics, logging).

• If you find dynamic keys ("prefix-" + id, `flag-${id}`), the verdict is blocked. Stop and ask the user how to proceed; automated removal can't be complete.
• If you find no hits, the flag may live in another repo or only in a flag set. That is caution.

Phase 5: Present the plan and wait

Show:

• the forward treatment for each critical environment and why;
• each call site with the branch to keep and the code to delete;
• the verdict, with every caution reason;
• the last impression for each critical environment.

If the forward treatment is control or a killed defaultTreatment, say plainly that the newer code path will be deleted. Edit nothing until the user explicitly confirms this plan.

Phase 6: Edit and verify

1. Work on a new branch in the application repo.
2. At each call site, keep the forward branch and inline the config value if WithConfig is used. Remove the dead branches, plus any flag-only constants, wrappers, imports, tests, fixtures, localhost or offline entries, and docs. Don't refactor unrelated code.
3. Search again for the key and for the batch and flag-set patterns. Any remaining hits must be explained: homonyms, other services, or fixtures the user wants to keep.
4. Run the repo's own build, lint and tests. Fix any failures before moving on.

Phase 7: Open the PR

Confirm with the user before pushing or opening the PR. Use the repo's normal tooling and its own PR template and conventions (for example .github/pull_request_template.md or CONTRIBUTING). Don't impose a format. Whatever the template, the description must capture:

• the flag key and the treatment (or config value) that was kept;
• the FME evidence: org and project, critical environments checked, the forward treatment (and config value, if WithConfig is used) in each, the verdict and any caution the user acknowledged, the experiment check result, and the last impression in each critical environment;
• what was removed: branches, tests, config, imports;
• how it was verified: the clean search and the build and test run;
• which repo(s)/service(s) were searched — a clean search here does not prove the flag is unused elsewhere;
• the follow-up: archive the flag with manage-flag-lifecycle once this change is deployed everywhere the flag is evaluated, plus any other repos or services that may still reference it.

Phase 8: Hand off

Report the PR link and the follow-up: "After this deploys, use manage-flag-lifecycle to archive <flag>." Don't archive or delete here.

Examples

• "Remove new-checkout-flow from this repo": verdict, plan, confirm, edit, verify, PR, then the archive hand-off.
• "Hardcode the winning treatment for dark-mode": resolve the forward treatment from the live definitions, not from the code.
• "This flag is killed in prod, clean it up": the forward treatment is defaultTreatment; warn that the new path is deleted.
• "Which flags can we clean up?": hand off to discover-feature-flags (stale audit).
• "Archive the flag too": PR here first, then manage-flag-lifecycle after the deploy.

Performance Notes

• One complete paginated List flag definitions inventory covers the environments; it may require multiple calls. A page is not the whole inventory.
• Search the flag key first, then the batch and flag-set patterns. Wrappers often hide the literal key.
• Keep the diff to the flag. Unrelated refactors make the PR harder to review and revert.

Troubleshooting

Issue	Action
Critical environments disagree	blocked. Ask the user to align targeting (update-flag-targeting) or narrow the critical set.
An environment has no definition	Its forward treatment is control, so the fallback branch is live there. Treat it as caution and confirm.
Flag is already archived but still in code	Allowed. The forward treatment is control; confirm the fallback branch is what users get today.
ACTIVE experiment on the flag	blocked. Finish it first (manage-experiments).
Code uses WithConfig	Hardcode the treatment's config value from the definition, not just the name. If critical environments share the treatment name but have different config values, that's blocked, not ready — hardcoding would silently diverge environment behavior.
No explicit critical environment set	Stop and ask. Don't default to "ready" on an empty or unconfirmed critical set.
Only one repo searched	Record that scope in the PR and summary. Don't claim the flag is fully unused until other repos/services are confirmed or searched.
Dynamic flag keys	blocked. Stop and ask the user.
No call sites found	caution. Check other repos and flag sets before claiming the flag is unused.