catalog / services

Feature Flag Service

Evaluate flags per user with targeting, rollouts and audit.

18 capabilities 2 sections reference specification

Build against it

# give your agent the catalog — no account, no install
claude mcp add provespec -- npx -y provespec-mcp

# then, from any agent session
spec_get(slug: "feature-flags")                → the capability tree
spec_checklist(slug: "feature-flags")          → the questions to answer
spec_grade(slug: "feature-flags", grades: [...])  → parity % + the gap list

# or just fetch it
curl https://provespec.com/catalog/feature-flags/spec.json

Grade every capability below as yes · partial · no · na, with a file reference as evidence. Whatever you leave ungraded counts as missing — the gap list is the work queue.

Or just paste this to your agent

Use the ProveSpec MCP server. Fetch the "feature-flags" spec with
spec_get, then walk spec_checklist and grade this repository against it —
one verdict per capability, each with a file reference as the note.
Call spec_grade with the results and give me the gap list as the plan.

If the server is not registered, add it first:
  claude mcp add provespec -- npx -y provespec-mcp

The specification

AI 15

Flags

✓ Create, update, archive a flag keys are stable and unique
✓ Boolean and multivariate flags string, number or JSON variants
✓ Default value when nothing matches

Targeting

✓ Rules on user attributes country, plan, email domain ordered, first match wins
✓ Individual user overrides allow and deny lists
✓ Percentage rollout stable bucketing by user key
✓ Consistent bucketing across evaluations same user, same variant

Environments

✓ Separate values per environment dev/staging/prod

Evaluation

✓ Evaluate a single flag for a context
✓ Bulk evaluate all flags for a context one round trip per page load
✓ Local evaluation from a cached ruleset no network call per check

Delivery

✓ Streaming updates to connected SDKs SSE or websocket with polling fallback

Safety

✓ Kill switch takes effect immediately

Audit

✓ Change log of who changed what, when
✓ Evaluation metrics per flag and variant

UI 3

Console

✓ Flag list with environment and state
✓ Rule editor with a live preview of who matches
✓ Change history with diff and rollback

Download spec.json All 53 specs