@kud/mcp-harness-fme

<div align="center">

MCP server for Harness FME (Split.io) — read and toggle feature flags.

<a href="https://kud.io/projects/mcp-harness-fme">Website</a> · <a href="https://kud.io/projects/mcp-harness-fme/docs">Documentation</a>

</div>

Features

• 28 tools — covers workspaces, environments, feature flags, flag definitions, segments, rule-based segments, and change requests.
• Kill & restore — instantly kill a flag to force all traffic to the default treatment, or restore it with a single tool call.
• Safety guard — every destructive operation (delete, kill, archive, disable) requires confirm: true, preventing accidental changes.
• Rule-based segments — create, update, enable, disable, and submit change requests for rule-based segments per environment.
• Change request flow — submit segment definition changes with optional approvers for teams that require approval gates.
• Zero-config startup — reads MCP_HARNESS_FME_API_KEY from the environment and exits immediately if it is missing.

Install

Add to your MCP client config (see Usage below), or install globally to run manually:

npx --yes @kud/mcp-harness-fme@latest

Set the environment variable MCP_HARNESS_FME_API_KEY to your Harness FME API key before starting the server.

Usage

Claude Desktop / Claude Code

{
  "mcpServers": {
    "harness-fme": {
      "command": "npx",
      "args": ["--yes", "@kud/mcp-harness-fme@latest"],
      "env": {
        "MCP_HARNESS_FME_API_KEY": "your_api_key"
      }
    }
  }
}

For Claude Code, add via the CLI:

claude mcp add --transport stdio --scope user harness-fme \
  --env MCP_HARNESS_FME_API_KEY=your_api_key \
  -- npx --yes @kud/mcp-harness-fme@latest

Available tools

Tool	Description
list_workspaces	List all FME workspaces in the account
list_environments	List all environments in a workspace
list_traffic_types	List all traffic types in a workspace
list_rollout_statuses	List rollout status definitions for a workspace
list_feature_flags	List feature flags in a workspace (filter by tag, status, name)
get_feature_flag	Get metadata for a specific feature flag
create_feature_flag	Create a new feature flag for a given traffic type
update_feature_flag	Update a flag's description, tags, owners, or rollout status
delete_feature_flag	Permanently delete a feature flag (confirm: true required)
archive_feature_flag	Archive a flag, removing it from active use (confirm: true required)
unarchive_feature_flag	Restore a previously archived feature flag
kill_feature_flag	Kill a flag in an environment — forces default treatment (confirm: true required)
restore_feature_flag	Restore a killed feature flag in an environment
list_flag_definitions	List flag targeting rules in an environment
get_flag_definition	Get treatments and targeting rules for a flag in an environment
create_flag_definition	Activate a flag in an environment with treatments and targeting rules
update_flag_definition	Fully replace a flag's targeting rules in an environment
delete_flag_definition	Remove a flag's targeting rules from an environment (confirm: true required)
list_segments	List all segments in a workspace
list_rule_based_segments	List all rule-based segments in a workspace
get_rule_based_segment	Get a rule-based segment's workspace-level metadata
create_rule_based_segment	Create a new rule-based segment in a workspace
delete_rule_based_segment	Permanently delete a rule-based segment (confirm: true required)
list_rule_based_segment_definitions	List rule-based segment definitions in an environment
update_rule_based_segment_definition	Update a rule-based segment's rules in an environment
enable_rule_based_segment_definition	Activate a rule-based segment in an environment
disable_rule_based_segment_definition	Remove a rule-based segment from an environment (confirm: true required)
create_rule_based_segment_change_request	Submit a change request for a segment definition with optional approval flow

Development

git clone https://github.com/kud/mcp-harness-fme.git
cd mcp-harness-fme
npm install
npm run dev           # run from source with tsx
npm run inspect:dev   # MCP Inspector at http://localhost:5173
npm test              # vitest
npm run build         # compile to dist/

The server reads MCP_HARNESS_FME_API_KEY at startup and exits immediately if it is absent. All tools are defined in src/index.ts.

---

📚 Full documentation → mcp-harness-fme/docs