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Instructions

Implementation Reference

• packages/mcp/src/tools/failures.ts:18-38 (handler)

  The core business logic for fetching and formatting failure modes for a given service.

  export async function handleGetFailureModes(
    input: GetFailureModesInput,
    client: RhumbApiClient
  ): Promise<GetFailureModesOutput> {
    try {
      const score = await client.getServiceScore(input.slug);
      if (!score) return { failures: [] };
  
      return {
        failures: score.failureModes.map((fm) => ({
          pattern: fm.pattern,
          impact: fm.impact,
          frequency: fm.frequency,
          workaround: fm.workaround
        }))
      };
    } catch {
      // Resilient fallback: return empty array on any error
      return { failures: [] };
    }
  }

• packages/mcp/src/server.ts:104-116 (registration)

  Registration of the get_failure_modes tool in the MCP server instance.

  server.tool(
    "get_failure_modes",
    "Get known failure patterns, impact severity, and workarounds for a service. Use BEFORE integrating to write defensive code, or AFTER hitting an error to diagnose it.",
    {
      slug: z.string().describe(GetFailureModesInputSchema.properties.slug.description)
    },
    async ({ slug }) => {
      const result = await handleGetFailureModes({ slug }, client);
      return {
        content: [{ type: "text" as const, text: JSON.stringify(result) }]
      };
    }
  );

• packages/mcp/src/types.ts:93-112 (schema)

  Input schema and output type definitions for the get_failure_modes tool.

  export const GetFailureModesInputSchema = {
    type: "object" as const,
    properties: {
      slug: { type: "string" as const, description: "Service slug from find_services results (e.g. 'stripe'). Returns known failure patterns, impact severity, and workarounds." }
    },
    required: ["slug"] as const
  };
  
  export type GetFailureModesInput = {
    slug: string;
  };
  
  export type GetFailureModesOutput = {
    failures: Array<{
      pattern: string;
      impact: string;
      frequency: string;
      workaround: string;
    }>;
  };