List all FME workspaces in the account

List all environments in a workspace

List feature flags in a workspace

Get metadata for a specific feature flag

Get the targeting rules and treatment definition of a feature flag in a specific environment

Kill (disable) a feature flag in an environment — forces all traffic to the default treatment

Restore (re-enable) a killed feature flag in an environment

Create a new feature flag for a given traffic type

Update a feature flag's description, tags, or owners (partial update)

Permanently delete a feature flag from a workspace — irreversible

List all feature flag definitions (targeting rules) in a specific environment. Full definitions are large; pass summary: true to get name/id only when you just need to locate a flag.

Build a deep-link to a feature flag's definition in the Harness FME web UI. Pass workspace, flag, and environment by name or id — the org slug, project, flag id, and env id are resolved for you. Requires MCP_HARNESS_FME_ACCOUNT_ID and MCP_HARNESS_FME_ORG_GUID env vars on the server (those IDs are not exposed by the API — copy them once from a flag URL in the browser).

Add a segment to a specific treatment of a feature flag via read-modify-write — safer than update_flag_definition's full replace, where a dropped field silently removes existing targeting. Idempotent: a no-op if the segment is already on the treatment. For workspaces where list_workspaces reports requiresTitleAndComments: true, pass title (and comment).

Create (activate) a feature flag definition in a specific environment with treatments and targeting rules. For workspaces where list_workspaces reports requiresTitleAndComments: true, pass title (and comment) or the API rejects the write with a 400.

Fully replace a feature flag definition (treatments, targeting rules) in an environment. For workspaces where list_workspaces reports requiresTitleAndComments: true, pass title (and comment) or the API rejects the write with a 400.

Remove a feature flag definition from an environment — the flag itself remains, but loses its targeting rules in that environment

List all segments in a workspace

List all traffic types in a workspace

List rollout status definitions for a workspace (e.g. Killed, Permanent, Ramping) — use the returned IDs to filter feature flags by rollout status

Archive a feature flag — removes it from active use while preserving history. Subject to OPA policy checks (409 on failure).

Unarchive a previously archived feature flag, restoring it to active use

List all rule-based segments in a workspace

Get a rule-based segment's workspace-level metadata by name

Create a new rule-based segment in a workspace under a specific traffic type

Permanently delete a rule-based segment from a workspace — environment-level configs must be removed separately

List rule-based segment definitions in a specific environment

Update a rule-based segment definition in an environment (rules, exclusions, matchers)

Enable (activate) a rule-based segment in a specific environment — creates an empty definition that can then be configured via update

Disable (remove) a rule-based segment from a specific environment — workspace-level metadata is preserved

Submit a change request for a rule-based segment definition — supports approval flow via approvers