Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the full burden and does so: it discloses cost ($0.005/call via x402/USDC), that billing only occurs on delivery, that no API key or account is required, the 2000-character cap, and that long texts are split by sentence while preserving order and line breaks. That is exactly the kind of operational context an agent needs before paying for a call.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with the 'Use when...' trigger, then limits, chaining and pricing in a compact block with no filler sentences. The payment-mechanism detail (x402/USDC) is slightly dense but still decision-relevant.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

No output schema and no annotations exist, and the description covers cost, limits, segmentation behavior and chaining, which is most of what matters. It never states what the response looks like (translated string vs object, detection result), which is the one remaining gap for a no-output-schema tool.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so all three parameters are already documented, including ISO-code-or-English-name for 'to' and auto-detection for 'from'. The description restates these facts and adds no syntax, format or constraint details beyond the schema, so the baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

Names a specific verb (translate), the resource (text), the engine (Meta M2M100 1.2B) and the scope (about 100 languages), so an agent knows exactly what it gets. It does not explicitly say why an agent would pick this over llm_completion or chat_completions for translation, so sibling differentiation is only implied by the tool's exclusivity.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

'Use when an agent must say something in a language it was not given' is a concrete trigger condition, and the chaining note with /v1/ai/transcribe and /v1/ai/speech tells the agent where this fits in a pipeline. There is no explicit when-not guidance (e.g. against using a general LLM for translation).

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.