impact

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

The description adds valuable behavioral context beyond the annotations: it specifies traversal along 'reverse hard edges' and that it computes 'related diagnostic rules'. This clarifies what the tool actually does internally. It aligns with the readOnlyHint (read-only) and idempotentHint, with no contradictions, and deepens the agent's understanding of its behavior.

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 a single, well-structured sentence that front-loads the core purpose and key behavioral aspects. It contains no filler or redundancy, efficiently conveying the tool's function in minimal words.

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?

Although an output schema exists, the description does not explain the input parameters or how to invoke the tool correctly. The agent is left without clarity on what 'ref', 'change', and 'max_depth' should contain or how they affect the computation. Given the zero schema coverage and missing parameter explanations, the description is insufficient for confident correct invocation.

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 0%—none of the three parameters (ref, change, max_depth) are described in the schema, and the description does not explain their semantics either. The description only hints that 'change' is a field change, but it does not specify what 'ref' refers to, the structure of 'change', or how 'max_depth' is used. Since the description fails to compensate for the absent parameter documentation, the agent receives minimal guidance.

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 clearly states the tool's function: read-only precomputation of nodes and diagnostic rules affected by a hypothetical field change along reverse hard edges. It uses a specific verb ('precompute') and resource ('nodes and diagnostic rules'), making the purpose understandable. However, it does not explicitly distinguish itself from sibling tools like 'check' or 'trace', relying on the unique 'impact' focus.

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 implies usage for analyzing the impact of hypothetical changes (before committing), but it does not explicitly state when to use this tool versus alternatives or provide exclusions. There is no mention of when not to use it or what other tools might be better for different scenarios, so guidance is implied rather than explicit.

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