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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered. The description adds one genuine behavioral fact — this returns metadata rather than file content — but stops there, saying nothing about pagination, size limits, or failure behavior on a missing ID.

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?

A single six-word sentence with zero redundancy and the resource stated first. It is efficiently sized, though the extreme brevity leaves no structure to speak of beyond the one clause.

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?

There is no output schema, so the description is the only place an agent could learn the shape of the returned metadata, and it does not say what fields come back or what a failed lookup returns. For a simple single-parameter read tool the gap is modest but real.

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% and there is a single required parameter, so the schema already carries parameter meaning; baseline is 3. The description adds only that the ID refers to a ProteinIQ file, which the schema field text already states.

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 gives a specific verb and resource ('Fetch metadata for one ProteinIQ file'), and the word 'metadata' usefully distinguishes it from a content-retrieval sibling like read_file. However, it never names or contrasts with list_files or read_file, so the agent must infer the boundary between listing, reading content, and reading metadata.

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?

There is no guidance on when to use this tool versus list_files (to discover IDs) or read_file (to get file contents). No prerequisites, no mention of what happens when the file_id is unknown or the file is inaccessible.

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