identify_file_type

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

The description adds context by explaining the underlying mechanism (magic numbers/file signatures), which is beyond the annotations (readOnlyHint=false). It does not mention potential side effects or error conditions, but the tool is likely a pure computation with no side effects.

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, front-loaded sentence that efficiently conveys the core functionality with no wasted words.

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?

While the description correctly identifies the tool's purpose, it lacks information about the output or return format. Given no output schema, the agent is left to infer what the tool returns (e.g., MIME type, file extension). This gap reduces completeness for agent decision-making.

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 does not add additional meaning beyond the schema, as it only states the tool's purpose without elaborating on parameter usage or constraints.

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 action (identify file type) and the method (based on magic numbers/file signatures). It is distinct from sibling tools, such as convert or analyze, as no other tool specifically identifies file types from raw data.

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 usage when needing to determine a file type from header data, but provides no explicit guidance on when to use it versus alternatives, nor any exclusions or prerequisites.

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