Flipt MCP Server

Implementation Reference

• src/index.ts:637-675 (handler)

  MCP tool handler for 'evaluate_boolean_flag'. Validates inputs with Zod schema and delegates to FliptClient.evaluateBoolean, returning the response or error.

  server.tool(
    'evaluate_boolean_flag',
    {
      namespaceKey: z.string().min(1),
      flagKey: z.string().min(1),
      entityId: z.string().min(1),
      context: z.record(z.string()).optional(),
    },
    async args => {
      try {
        const response = await fliptClient.evaluateBoolean(
          args.namespaceKey,
          args.flagKey,
          args.entityId,
          args.context
        );
  
        return {
          content: [
            {
              type: 'text',
              text: JSON.stringify(response, null, 2),
            },
          ],
        };
      } catch (error: any) {
        console.error('Error evaluating boolean flag:', error);
        return {
          content: [
            {
              type: 'text',
              text: `Failed to evaluate boolean flag: ${error.message}`,
            },
          ],
          isError: true,
        };
      }
    }
  );

• src/index.ts:639-644 (schema)

  Input schema (Zod) for the 'evaluate_boolean_flag' tool defining parameters: namespaceKey, flagKey, entityId, and optional context.

  {
    namespaceKey: z.string().min(1),
    flagKey: z.string().min(1),
    entityId: z.string().min(1),
    context: z.record(z.string()).optional(),
  },

• src/services/fliptClient.ts:649-667 (helper)

  Helper method in FliptClient that performs the boolean flag evaluation by calling the generated EvaluationServiceApi.

  async evaluateBoolean(
    namespaceKey: string,
    flagKey: string,
    entityId: string,
    context: Record<string, string> = {}
  ) {
    try {
      const response = await this.evaluationApi.evaluateBoolean({
        namespaceKey,
        flagKey,
        entityId,
        context,
      });
      return response;
    } catch (error) {
      console.error('Error evaluating boolean flag:', error);
      throw error;
    }
  }