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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds the behavioral detail that results indicate read/write capability, which is useful. However, it doesn't disclose details like pagination behavior, default limit, or how the 'limit' parameter interacts with results, though the schema covers the limit parameter.

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?

The description is a single, well-structured sentence that front-loads the main action and includes the key differentiator (read/write support). It is concise and every part adds value.

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?

The tool has an output schema, so return values are documented. The description covers the search criteria and the read/write capability. It could be more complete by explicitly mentioning the 'limit' parameter's effect or the default behavior when query is omitted, but the schema covers those. Overall, it's adequate for an agent to use the tool correctly.

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 80%, so most parameters are already documented in the schema. The description adds the overall search criteria (extension, name, MIME type, category) and the read/write capability filter, which maps to can_read and can_write. However, it doesn't add much beyond what the schema already provides for individual parameters.

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 clearly states the tool's purpose: searching file formats by extension, name, MIME type, or category, and determining read/write support. It uses a specific verb ('search') and resource ('file formats'), and the mention of read/write capability distinguishes it from a simple format list.

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?

The description implies when to use this tool: when you need to search formats by various criteria and see read/write support. It doesn't explicitly name alternatives like check_conversion or list_conversion_targets, but the context signals show siblings, and the description's focus on search and read/write capability provides clear context. It lacks explicit 'when not to use' guidance.

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