Flipt MCP Server

Implementation Reference

• src/index.ts:280-344 (handler)

  Primary handler and registration for the 'update_flag' MCP tool. Validates input with Zod schema, fetches current flag, applies updates, calls FliptClient.updateFlag, and returns formatted response.

  server.tool(
    'update_flag',
    {
      namespaceKey: z.string().min(1),
      key: z.string().min(1),
      name: z.string().min(1),
      description: z.string().optional(),
      enabled: z.boolean().optional(),
    },
    async args => {
      try {
        const currentFlag = await fliptClient.getFlag(args.namespaceKey, args.key);
        if (!currentFlag) {
          return {
            content: [
              {
                type: 'text',
                text: `Flag ${args.key} in namespace ${args.namespaceKey} not found`,
              },
            ],
            isError: true,
          };
        }
  
        // update changed fields
        const updatedFlag = {
          ...currentFlag,
          name: args.name || currentFlag.name,
          description: args.description || currentFlag.description,
          enabled: args.enabled || currentFlag.enabled,
        };
  
        const flag = await fliptClient.updateFlag(
          currentFlag.namespaceKey!,
          currentFlag.key!,
          updatedFlag.name!,
          updatedFlag.description,
          updatedFlag.enabled
        );
  
        return {
          content: [
            {
              type: 'text',
              text: JSON.stringify(flag, null, 2),
            },
          ],
          _meta: {
            uri: `flipt://namespaces/${args.namespaceKey}/flags/${args.key}`,
          },
        };
      } catch (error: any) {
        console.error('Error updating flag:', error);
        return {
          content: [
            {
              type: 'text',
              text: `Failed to update flag: ${error.message}`,
            },
          ],
          isError: true,
        };
      }
    }
  );

• src/index.ts:282-288 (schema)

  Zod input schema for the update_flag tool parameters.

  {
    namespaceKey: z.string().min(1),
    key: z.string().min(1),
    name: z.string().min(1),
    description: z.string().optional(),
    enabled: z.boolean().optional(),
  },

• src/services/fliptClient.ts:162-180 (helper)

  FliptClient helper method that wraps the generated FlagsServiceApi.updateFlag to perform the actual flag update via Flipt API.

  async updateFlag(
    namespaceKey: string,
    key: string,
    name: string,
    description?: string,
    enabled?: boolean
  ) {
    try {
      const response = await this.flagsApi.updateFlag(namespaceKey, key, {
        name,
        description,
        enabled,
      });
      return response;
    } catch (error) {
      console.error('Error updating flag:', error);
      throw error;
    }
  }

• src/handlers/toolHandlers.ts:165-200 (helper)

  Alternative handler implementation in ToolHandlers class (possibly unused), which directly calls FliptClient.updateFlag.

  async handleUpdateFlag({
    namespaceKey,
    key,
    name,
    description,
    enabled,
  }: {
    namespaceKey: string;
    key: string;
    name: string;
    description?: string;
    enabled?: boolean;
  }) {
    try {
      const flag = await this.fliptClient.updateFlag(namespaceKey, key, name, description, enabled);
      return {
        content: [
          {
            type: 'text',
            text: `Successfully updated flag: ${JSON.stringify(flag, null, 2)}`,
          },
        ],
      };
    } catch (error) {
      console.error(`Error updating flag ${key} in namespace ${namespaceKey}:`, error);
      return {
        content: [
          {
            type: 'text',
            text: `Error updating flag ${key} in namespace ${namespaceKey}: ${error}`,
          },
        ],
        isError: true,
      };
    }
  }

• src/generated/api/models/UpdateFlagRequest.ts:1-50 (schema)

  Generated TypeScript interface for UpdateFlagRequest used by the Flipt API client.

  /**
   * api
   * No description provided (generated by Openapi Generator https://github.com/openapitools/openapi-generator)
   *
   * OpenAPI spec version: 1.47.0
   * 
   *
   * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
   * https://openapi-generator.tech
   * Do not edit the class manually.
   */
  
  import { HttpFile } from '../http/http';
  
  export class UpdateFlagRequest {
      'key'?: string;
      'name': string;
      'description'?: string;
      'enabled'?: boolean;
      'namespaceKey'?: string;
      'defaultVariantId'?: string;
      'metadata'?: any;
  
      static readonly discriminator: string | undefined = undefined;
  
      static readonly mapping: {[index: string]: string} | undefined = undefined;
  
      static readonly attributeTypeMap: Array<{name: string, baseName: string, type: string, format: string}> = [
          {
              "name": "key",
              "baseName": "key",
              "type": "string",
              "format": ""
          },
          {
              "name": "name",
              "baseName": "name",
              "type": "string",
              "format": ""
          },
          {
              "name": "description",
              "baseName": "description",
              "type": "string",
              "format": ""
          },
          {
              "name": "enabled",
              "baseName": "enabled",
              "type": "boolean",