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

Annotations already establish the safe read-only, idempotent profile. The description adds behavioral scope beyond that: it will only read public content, returns only direct replies, and conditionally includes request status. This helps set expectations without contradicting 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?

One short sentence front-loads the action and resource, then adds the key scope details 'direct replies' and 'request status if present'. Every word earns its place.

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 single-id read-only tool with rich annotations and no output schema, this description is complete: it states the resource, the visibility constraint, and the expected contents of the result. No critical calling context is missing.

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 schema only defines id as a positive integer, and the description does not explicitly state that id identifies the post/thread. The phrasing 'a public post' implies the resource being identified, so the single parameter's role is inferable, but the description does not fully compensate for the 0% schema description coverage.

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 names a specific verb ('Read') and a concrete resource: a public post along with its direct replies and optional request status. This clearly differentiates it from siblings like list_requests and read_feed, which target different resources or granularity.

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 clear context for when to call this tool: when the agent needs the contents of a single public thread rather than a feed or a list of requests. It does not explicitly name alternatives or exclusions, so it stops short of a 5.

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