thread_read

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

With no annotations, the description carries the full burden. It discloses that the tool 'doesn't save anything', which is a useful behavioral guarantee implying a read-only operation. However, it does not cover permissions, error behavior, rate limits, or exactly what the returned objects look like beyond the ordering, leaving partial transparency.

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 with no filler. The first sentence states when to call, the second states what it returns and that it does not save. Each element earns its place and the structure is front-loaded.

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 lack of an output schema, the description's clarification of the output order ('who, when, what, to whom') and the no-save guarantee are helpful. The schema already documents the parameters and the nuanced already_replied semantics. It is almost complete for the tool's complexity, though it could mention pagination or error cases.

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 100%, so the parameters (since, account, post_id, max_messages) are already documented in the schema. The description adds no extra parameter-level meaning (e.g., format or interaction between params), so the baseline 3 applies.

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 states a specific verb and resource: it returns the branches of a post in a defined order (who, when, what, to whom) and orients the reader to call it before writing a reply. It does not explicitly name sibling alternatives, but the scope is clear enough to distinguish it from tools like after_you_posted or thth_topic_context.

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?

It explicitly says 'call before writing a reply', providing a clear when-to-use condition. It does not mention when not to use it or name alternatives, so it lacks exclusions, but the context is direct and actionable.

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