send_file

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

With no annotations, the description carries the full behavioral burden and does not disclose size limits, auth/permission requirements, whether the file is uploaded or referenced by URL, synchronous behavior, or failure modes. It only adds the filePath/fileUrl exclusivity, which is closer to parameter semantics than behavior. For a mutation tool with zero annotation coverage this is a significant gap.

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?

One dense sentence plus a short constraint clause, front-loaded with the action and resource and with zero filler. Every element earns its place.

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?

For a write/send operation with no annotations and no output schema, the definition covers the minimum (target chatMid, source choice, supported types) but omits limits, error behavior, and what happens on success. Adequate but with clear gaps.

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 100%, so baseline is 3, but the description goes beyond the schema by asserting that filePath and fileUrl are alternatives and that one is needed — the schema marks neither as required, so this adds genuine meaning. It does not explain syntax or precedence when both are supplied.

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?

States a specific verb (send) and resource (file) and enumerates supported types (PDF, Word, Excel, ZIP, video, audio), which distinguishes it from send_message and send_image in the sibling list. It does not explicitly name those siblings as alternatives, so it stops short of a 5.

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 clause 'specify either filePath or fileUrl' gives a real selection rule for the two source parameters, but there is no guidance on when to use this tool versus send_image, send_message, or download_message_file, nor any stated prerequisites or constraints.

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