list_spaces

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

With no annotations provided, the description carries the full burden. It does disclose that the operation is a read-only listing scoped to spaces the user can access, and it states the return is a formatted string. However, it does not disclose pagination behavior, how space_type filtering behaves, or any authentication requirements, so behavioral context remains thin.

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 compact and front-loaded, which is good. However, the second sentence ('A formatted list of Google Chat spaces accessible to the user') largely restates the first, and since an output schema exists, the Returns section adds marginal value while occupying space that could have documented the parameters.

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 tool with 3 parameters, 0% schema coverage, and no annotations, the description is incomplete. The optional parameters page_size and space_type are left unexplained (what values does space_type accept besides the default 'all'?), and pagination behavior is not described. The purpose and return type are covered, but the agent cannot determine optional parameter semantics.

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 0%, so the description must compensate. It connects 'accessible to the user' to the required user_google_email parameter and hints at space_type values via '(rooms and direct messages)', but page_size is entirely undocumented in both schema and description, leaving a real gap.

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 uses a specific verb ('Lists') with a specific resource ('Google Chat spaces') and clarifies scope with '(rooms and direct messages)' and 'accessible to the user'. This clearly distinguishes it from message-level Chat siblings like get_messages, send_message, and search_messages, leaving no ambiguity about what it does.

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 provides no guidance on when to choose this tool over alternatives — no when-to-use context, no prerequisites, and no exclusions. An agent would have to infer the use case entirely from the purpose statement, which is minimal guidance at best.

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