Send file

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

The description discloses meaningful runtime behavior not present in the annotations: multipart/form-data upload, the 10MB native-image threshold, 7-day download-link expiry for larger files, the 100MB maximum, and a concrete supported-format list. It does not describe return values, failure modes, rate limits, or authentication requirements, but the basic mutating nature is already signaled by readOnlyHint=false.

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 front-loaded with the core purpose, then moves to usage trigger, file-source constraint, and supported formats/limits; there is little filler. The slight redundancy comes from listing the media types twice in the first two sentences, and the 'via WhatsApp or Telegram' phrasing creates a minor inconsistency with the routing parameter mentioned in the schema.

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 19-parameter send tool with no output schema, the input semantics are largely covered by the schema plus this description. However, the description does not state what the call returns, how delivery failures are reported, or which channels actually support file sending versus link fallback. The 'via WhatsApp or Telegram' framing also leaves dispatch_routing values like sms, notify, and max unexplained, so an agent may not fully understand the routing options.

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 the baseline is 3; the schema already documents all 19 parameters. The description adds value by introducing a critical one-of constraint: 'exactly one of: file_path, file_url or file_base64 (with file_name)', plus the size and format whitelist. It does not enrich the routing/scheduling parameters beyond the schema, but the added constraints meaningfully improve parameter selection.

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 and resource: 'Send a file (document, image, audio, video, contact) to a recipient via WhatsApp or Telegram.' It also enumerates the supported media types, which makes the tool's purpose obvious. However, the stated channel scope is narrower than the schema's dispatch_routing enum, which includes whatsapp, tdlib, telegram, notify, max, and sms, so the purpose is clear but not perfectly aligned with the schema.

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 an explicit usage trigger: 'Use it when the user wants to share a document, photo, voice message, video or contact card.' It also gives concrete guidance on file sourcing: 'Provide the file as exactly one of: file_path, file_url or file_base64.' It references send_message for recipient rules, but it does not explicitly state when not to use this tool or name send_message for plain-text messages, so it stops just short of full exclusion guidance.

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