download_file

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

Annotations already establish the tool as read-only and idempotent. The description adds valuable behavioral context beyond annotations: it returns content as base64, has a 50 MiB limit, and reads from the controlled computer. However, it does not disclose error behavior for missing files or size violations, though annotations lower the burden.

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, concise sentence starting with the verb 'Read', containing no fluff or redundant repetition. It efficiently packs the key details: file, location, encoding, and size limit.

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?

Together with the annotations (read-only, idempotent, non-destructive) and an output schema, the description covers the essential behavior of the tool: retrieving a file's content as base64 with a 50 MiB cap. It omits failure modes (e.g., file not found, size exceeded) and path resolution details, but for a single-purpose file-read tool with strong annotations, this is largely adequate.

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?

The input schema describes 'path' as 'Source path on the controlled computer', but the tool description does not add further detail about the parameter (e.g., accepted path formats, absolute vs relative, permissions). With schema description coverage reported as 0%, the description fails to compensate by not explicitly addressing the path parameter beyond implying it identifies a file.

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 uses a specific verb ('Read'), identifies the resource ('file from the controlled computer'), and specifies the output format ('as base64') and size limit ('up to 50 MiB'). This clearly distinguishes it from sibling tools like upload_file, which performs the reverse operation.

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 file content from the controlled computer and imposes a size limit, but it does not explicitly state when to use this tool over alternatives or mention exclusions. For example, it does not reference upload_file or note that files over 50 MiB should be handled differently.

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