upload_media

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

Since no annotations are provided, the description carries the burden of disclosing behavior. It explains the upload action, the returned mediaId, and file size restrictions, but lacks details on authentication requirements, failure behavior, or idempotency.

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 two sentences, front-loaded with the primary action and outcome, followed by constraints. Every sentence provides value and there is no redundancy or 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?

For a simple upload tool with complete schema coverage and no output schema, the description covers the essential context: when to use it, what it returns, and what constraints apply. It could mention error scenarios, but overall it is sufficiently complete.

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% for the two parameters, so the schema already documents them sufficiently. The description adds file type and size constraints, which are helpful but not necessary for understanding individual parameters.

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 tool's function: 'Upload a local media file to DingTalk and get a mediaId.' It uses a specific verb ('Upload') and resource ('media file'), and distinguishes it from sibling tools that send messages.

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 explicitly states when to use the tool: 'Required before sending image, file, audio, or video messages.' It also provides file type and size limits, giving clear context for usage. However, it does not explicitly reference sibling tools or state when not to use it.

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