An MCP server that aggregates multiple downstream tools (text-to-speech, image generation, translation) via a Cloudflare Worker, exposing them through a single SSE endpoint with shared-secret authentication.
Three tools with complete input schemas and descriptions, but descriptions are generic and lack LLM-optimized guidance. All tools have proper Zod validation with constraints (min/max length, numeric bounds). However, descriptions do not explain WHEN to use each tool, dependencies, or recovery paths. Output schemas are partially documented in code but not formally declared. No error handling guidance for downstream service failures. Tool names follow verb_noun convention correctly.
Generate audio using ElevenLabs text-to-speech service
Generate images using a remote image generation service (Stable Diffusion, DALL-E, or custom)
Translate text to a target language
Descriptions lack LLM-optimized guidance. All three descriptions are 60-80 chars, below the 194-char baseline for production tools. Missing WHEN to use, prerequisites, and error recovery hints.
No output schema documentation. Code shows responses return content arrays with type/url/text fields, but this structure is not formally declared in tool metadata. LLMs cannot plan downstream calls without knowing response shape.
No error handling guidance. Tools call external services (ElevenLabs, image API, translator) but throw raw errors on failure. LLMs receive no recovery hints (retry, fallback, user action).
| Scored | Grade | Overall | Spec posture | Rubric |
|---|---|---|---|---|
| 2026-09-23 | D | 56 | 2026-07-28+ | v2 |
Parameter descriptions lack format/constraint details. 'voiceId' and 'modelId' have no guidance on valid values or format. 'targetLang' states '2-character ISO 639-1' but does not clarify case sensitivity or list examples.
No idempotency guarantees documented. Image generation and TTS are inherently non-deterministic (different outputs on retry). Tool descriptions should warn agents not to retry on transient failures without user confirmation.