send_image

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

With no annotations, the description carries the full behavioral burden, yet it only says what is sent and from where. It is silent on authentication requirements, whether the local file is uploaded or read remotely, size/format limits, failure modes, and whether the recipient must already be a contact or member of the chat.

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?

A single front-loaded sentence carrying the action, the target, and the parameter constraint with no filler or repetition.

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 three-parameter tool with no annotations and no output schema, the description covers the action and the source modes adequately. It remains thin on behavioral expectations (delivery result, error conditions) that an agent would need when the call fails or the image is rejected.

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 coverage is 100%, so the baseline is 3, but the description adds a genuine semantic constraint absent from the schema: the two optional source parameters are alternatives ('one of the two'), which cannot be derived from the property definitions alone.

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 and resource: send an image to a chat room or individual recipient, which is clearly distinct from text messaging or non-image file sending. However, it does not explicitly contrast itself with the sibling send_file, which plausibly also transmits binary content, so sibling differentiation is only partial.

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 gives one concrete usage rule — supply either filePath or imageUrl, not both — which is implied mutual exclusivity. It offers no guidance on when to pick this tool over send_file or send_message, so tool-selection context must be inferred from the name alone.

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