Get File Info

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

Annotations already declare readOnly, idempotent, and openWorld behavior. The description adds important scope beyond that: it returns metadata only and does not download content, which prevents a common misuse. It does not describe error handling or permission requirements, but the core behavioral boundary is disclosed.

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?

Two short sentences, front-loaded with the core action and immediately followed by the key limitation. Every phrase earns its place, with no redundant restatement of the tool name or schema.

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?

For a one-parameter read-only tool with an output schema and full annotation coverage, the description supplies everything needed to select and call the tool correctly: what it returns (metadata), what it does not return (content), and where the ID originates.

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 100%, so the baseline is 3. The description goes slightly beyond the schema by indicating where to obtain the file_id (a post's file_ids), which is genuinely useful context for constructing the call.

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?

The description names a specific verb and resource ('Get metadata of a file') and clarifies scope by tying the file to a post via file_ids. It does not explicitly differentiate from a sibling, but no sibling tool handles file metadata, so the ambiguity is low.

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?

It gives clear context for use (retrieving file metadata) and a useful negative constraint ('The file content is not downloaded'), which steers agents away from expecting bytes. It stops short of describing when to use an alternative or any prerequisites, but no direct alternative exists.

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