send_file

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

Discloses temporary directory usage, cleanup after upload, support for any file type, 60-second timeout, and that it mutates chat. Adds value beyond annotations.

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?

Two concise paragraphs, front-loaded with main purpose, then behavioral details and alternatives. No fluff.

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?

Covers essential behavioral details and usage distinctions, but lacks explicit parameter descriptions for all four parameters. Output schema absent but acceptable given tool simplicity.

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 has 0% description coverage; description mentions file_url and file_name (optional) and target_type (defaults group), but does not explain 'target' parameter (group ID vs friend ID). Partial clarity.

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?

Clearly states it downloads a file from a URL and sends to QQ group/friend. Distinguishes from siblings by naming send_message, send_image, send_voice for alternative content types.

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?

Explicitly states when to use (download and send file from URL) and when not (text, image, audio). Mentions requirement of publicly accessible URL without auth.

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