gmail_get_thread

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

Description discloses additional behaviors beyond annotations: 'Private content is returned only on the fresh response and is not replayable' and 'always fetches fresh provider data', plus the intentional omission of idempotency_key. These enrich the readOnlyHint and idempotentHint annotations.

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?

Two short paragraphs, efficient and to the point, no redundancy.

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?

While behavioral aspects are covered, the description omits explanations of required parameters and the output schema, leaving critical usage context unanswered.

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 has 7 parameters with 0% description coverage, and the description does not explain any parameters except indirectly implying max_messages via 'up to ten messages'. Required params like project_id, project_ref, connector_account_ref are 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?

Description states 'Read up to ten messages from one exact Gmail thread', clearly identifying the action, resource, and scope. It distinguishes from sibling tools by specifying the read nature and the limit.

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?

Description provides behavioral details (fresh data, private response) but does not explicitly state when to use this tool over alternatives or provide selection criteria.

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