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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds useful context about baseline comparison and return semantics, but it does not describe important behavioral details such as what happens with invalid baselines, how 'structural difference' is represented, or whether large diffs are truncated. No contradiction with annotations exists.

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?

The description is short and front-loaded with the core purpose, and most sentences carry useful information. However, the final 'Example: call introspection_system_diff with arguments {}' is not a real example and is misleading because the tool requires four non-empty arguments. That sentence wastes the only illustrative slot and introduces confusion.

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?

The tool has four required parameters, zero output schema, and no return-shape details. The description covers parameter meanings and states that the return is 'the structural difference between the two states,' but it does not explain what that structure looks like, what baseline_edge cases exist, or how to interpret the result. It is adequate for a simple diff-like tool but leaves gaps for an agent invoking it autonomously.

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?

With schema description coverage at 0%, the description carries the parameter-semantics burden, and it largely succeeds: it explains node_kind/node_id by referencing 'confidence,' fixes baseline_kind to 'since,' gives the baseline_iso_date format, and lists the source of valid node ids. This adds real meaning beyond the bare schema, though the 'same as confidence' reference is indirect and relies on sibling-tool knowledge.

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 opens with a specific action and resource: 'Compare a node's evidence against a baseline date.' It further clarifies the domain by pointing to 'introspection_system_list_nodes' for valid node ids and by naming the expected result as 'the structural difference between the two states.' It does not explicitly contrast with sibling tools, but the verb+resource is specific enough to distinguish it from most 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?

The description gives practical guidance by saying node_kind/node_id are 'same as confidence' and that valid ids come from introspection_system_list_nodes. It implies when the tool is appropriate—comparing a node against a baseline—but does not explicitly state when to use it instead of related introspection tools or mention exclusions.

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