Get a whole conversation, collapsed

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

With no annotations provided, the description carries the full burden and excels. It discloses quote stripping and token savings, ordering, threading logic, the null-return behavior when the required index is missing, message count/text caps, and the untrusted-content marking of message text. This is exemplary behavioral disclosure.

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?

Although lengthy, every sentence earns its place, covering rationale, usage, edge cases, limitations, and security. The structure front-loads the core purpose in the first sentence, then systematically expands. There is no fluff, and the length is proportionate to the tool's complexity.

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 tool's complexity, the description is complete: it explains the return value (thread messages, order, content), error behavior (null when no index), output limits, and the meaning of a degenerate thread. It also distinguishes from siblings. No output schema exists, so the description's coverage of return semantics is essential and well handled.

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 coverage is 100%, so the baseline of 3 applies. The description adds no specific parameter-level semantics beyond what the schema already provides; it doesn't discuss 'limit' or 'includeText' in prose. The schema itself is clear, so the tool remains adequately documented, but the description contributes no extra parameter value.

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 explicitly states the tool gets the entire thread for a single message, listing messages oldest first, with each message carrying only its sender's own text. It clearly differentiates from siblings by noting the collapsed nature and explicitly referencing get_email_body as an alternative, establishing a distinct, specific purpose.

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 explicit guidance: 'Prefer this over calling get_email_body once per message in a conversation.' It also clarifies the threading algorithm (RFC headers, not subject line), the behavior for single-message threads, and the critical prerequisite of a published body index, giving the agent clear conditions for when to use and when to avoid the tool.

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