Send Message

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

The annotations already indicate a non-read-only, non-idempotent write operation, and the description adds no additional behavioral traits. It does not disclose authorization needs, side effects, or error behaviors beyond the basic fact that a message is sent.

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 a single, front-loaded sentence with no filler or repetition. Every word contributes to identifying the core operation.

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 the five parameters, optional threading, likely authentication needs, and the large sibling set, the description is under-specified. It lacks routing context, auth prereqs, and thread semantics, though an output schema exists to cover return values.

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 only 40%, and the description does not compensate for the undocumented required parameters (user_google_email, space_id, message_text). It implies message_text is the content and space_id is the destination, but it leaves user_google_email's role and the distinction between thread_key and thread_name unexplained.

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 names a concrete action ('sends') and a specific resource ('Google Chat space'), which distinguishes it from the Gmail-sending sibling. It does not explicitly differentiate among Chat siblings like get_messages or create_reaction, but the verb+resource is specific enough for basic selection.

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?

There is no guidance on when to use this tool versus alternatives such as send_gmail_message or Chat read tools. No preconditions, caveats, or selection criteria are mentioned, leaving the agent to infer usage from the tool name and context.

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