download_file

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions the SFTP protocol and describes the return value, but doesn't cover important behavioral aspects like error conditions, timeout behavior, authentication requirements, file size limitations, or whether the operation is idempotent. The description provides basic operational context but lacks comprehensive behavioral transparency.

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 well-structured with clear sections (purpose, Args, Returns) and uses minimal sentences. Each sentence earns its place by providing essential information. The formatting is efficient, though the 'Args:' and 'Returns:' labels could be slightly more concise.

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?

Given the tool has an output schema (which handles return value documentation), no annotations, and 3 parameters with good description coverage, the description is reasonably complete. It covers the core operation, all parameters, and return format. The main gap is lack of behavioral context like error handling and authentication requirements, but the presence of output schema reduces the completeness burden.

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?

With 0% schema description coverage, the description compensates by clearly explaining all three parameters with examples and context. The Args section provides meaningful semantics: 'server' is explained with an example format, 'remote_path' specifies it must be absolute, and 'local_path' clarifies it's the destination. This adds substantial value beyond the bare schema.

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 specific action ('Download a file') and resource ('from a remote server via SFTP'), distinguishing it from sibling tools like upload_file. It provides a complete verb+resource+protocol combination that leaves no ambiguity about what the tool does.

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 provides no guidance on when to use this tool versus alternatives like upload_file or other sibling tools. It mentions SFTP protocol but doesn't specify prerequisites, authentication requirements, or when this tool is appropriate versus other file transfer methods. No exclusions or alternative scenarios are mentioned.

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