gmail_read_thread

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

Beyond the readOnlyHint annotation, the description discloses important edge-case behavior: missing bodies are reported as incomplete, and oversized or failed reads fail clearly. This adds operational transparency not covered by the 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 concise sentences front-load the primary action and scope, then add error behavior. No filler or redundant phrasing; every word contributes to understanding.

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 simple input schema and no output schema, the description covers the essential behavior and error handling. However, it omits any parameter explanation and does not clarify the 'bounded' limit or how missing bodies manifest, leaving minor gaps for an agent to fill from parameter names.

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?

The description does not explicitly explain any of the three parameters (threadId, accountId, maxMessages). It hints at accountId via 'explicit account' and maxMessages via 'bounded', but provides no direct mapping or detail, leaving schema coverage at 0%.

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 the verb 'read' and the resource 'Gmail thread', with explicit scope ('bounded', 'from an explicit account') and content detail ('including message-owned text bodies'). This distinguishes it from single-message reads and searches without needing to name siblings.

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?

Provides no explicit guidance on when to choose this tool over alternatives like gmail_read_message or gmail_search. The description implies its use case but does not state conditions or exclusions, leaving the agent to infer when a thread-level read is appropriate.

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