find_language

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

Annotations already cover the safety profile (readOnly, idempotent, closed-world), so the description's added value is the ranking behavior: exact codes, exact names, alternate names, then partial matches. That ranking is real behavioral context an agent cannot get from the schema, though it doesn't mention truncation behavior when results exceed limit.

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 verb and returned fields, followed by the routing advice and the ranking rule. Every sentence earns its place and there is no redundant restatement of the name.

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?

With an output schema present, the description needn't explain return structure, and it still usefully previews the key returned fields. An agent can call this correctly, with only the limit parameter's behavior left unaddressed.

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 coverage is 50%: the query parameter is well documented in-schema (name, alternate name, ISO 639-3, Glottocode, or 'wals:bsq' form), so the description rightly doesn't repeat it. But the limit parameter (max 25) is undocumented in both places, and the description says nothing about result capping, so it does not compensate for the gap.

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?

States a specific verb and resource ('Find languages by name or code') and immediately names what is returned (Glottocodes, family, macroarea, dataset coverage). That combination distinguishes it from siblings like filter_languages or language_profile without needing to open their schemas.

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?

Explicitly prescribes ordering against the other tools ('Use this before other tools when a name might be ambiguous') and gives a concrete motivating example ('Arabic' is a family; WALS has Arabic varieties). It lacks an explicit when-not clause or a named alternative for the unambiguous case, which keeps it from a 5.

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