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

Annotations already indicate idempotence and non-destructiveness; the description adds the concrete behavioral details that identical retries return the same receipt and that only one response is allowed per trace. This complements the annotations without contradicting them.

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?

Three short sentences deliver the core action, constraints, a safety directive, and idempotence behavior without redundant phrasing. The most important information 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?

For a simple two-parameter tool with no output schema, the description covers the essential invocation context, constraints, and repeat-call behavior. A minor gap is the inconsistent treatment of trace as optional in the description but required in the schema, which could confuse an agent.

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 only 50%: the trace parameter is described but statement has only constraints. The description clarifies that statement is a private reflection/criticism and reinforces the 1–4000 character limit, but it does not fully explain the relationship or optionality of the trace parameter, which the schema lists as required while the description implies optional.

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 action ('save'), a resource ('a reflection or criticism'), and a scoping condition ('private-to-owner', 'per trace'). This clearly differentiates it from sibling read/search tools and tells an agent what the tool is for.

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 frames the tool as a post-challenge, optional action, which is useful usage context. However, it does not explicitly say when to choose this over the sibling tools or when not to use it, so it stops short of full routing guidance.

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