send_image_as_user

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

With no annotations, description satisfactorily covers behavioral traits: explains user vs bot identity, wire format requirement, defaulting of thumbnail_key, and optional nature of metadata. Lacks some details like rate limits or error handling but sufficient.

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?

Single paragraph with clear front-loading of identity and purpose. Technical details are compact. Slightly verbose with version info, but overall efficient.

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 8 parameters and no output schema, description covers key aspects: prerequisite, wire format, defaulting, metadata role. Does not explain return value, but acceptable given tool type.

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?

Adds value beyond schema by explaining thumbnail_key defaults to image_key when omitted, and clarifies that width/height/mime/size are optional and auto-derived by Feishu. Schema coverage is 100% so baseline is 3, but description enhances understanding.

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 'Send an image as the logged-in user (NOT bot)', specifying the verb and resource. Distinguishes from sibling tools like send_message_as_bot and send_file_as_user.

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 mentions requirement of image_key from upload_image call and explains thumbnail_key defaulting behavior. Provides context for when to use, though does not directly compare to alternatives.

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