list_spaces

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

Discloses read-only nature via OAuth scope, notes no pagination token is exposed, and explains scope of results (only joined spaces). No annotations exist, so description carries full burden and meets it well.

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?

Five sentences, each adding unique value. Front-loaded with purpose. No redundancy or unnecessary verbosity.

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?

Covers purpose, usage, limitations, auth, and parameter details. Given the presence of an output schema (context signal), describing return values is unnecessary. Complete for a listing tool.

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 meaningful context beyond the schema: explains page_size default and Google hard cap, details space_type filter options, and notes pagination limitation. Schema coverage is 100% 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 'List Google Chat spaces' with specific verb and resource. Distinguishes from sibling tools by explaining its role in discovering space_id for get_messages, send_message, etc.

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 tells when to use ('discover the space_id needed for get_messages, send_message') and what it cannot do ('will not surface public spaces the user hasn't joined').

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