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

Beyond the readOnly/openWorld/idempotent annotations, the description adds crucial non-obvious behavior: 'no longer observed does not mean reinstated' and enrichment-only changes are excluded. This materially prevents misinterpretation of results and is exactly the kind of behavioral context an agent needs.

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 sentences with zero filler. The core action is front-loaded, and the second sentence delivers high-value caveats. 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?

The core concept is clear, but with 4 parameters, 0% schema coverage, and no output schema, the description omits important invocation details: pagination via limit/cursor, default to_generation behavior, and what the returned changes actually look like. This is not complete enough for fully self-contained use.

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 has 0% description coverage, so the description must compensate. It only indirectly references 'from_generation' and 'to_generation' as 'two retained snapshots' and provides no meaning for 'limit' or 'cursor', nor any default behavior for 'to_generation'. This leaves most parameter semantics to inference.

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 a specific action ('Compare two retained snapshots') and names the resource being compared. The caveat about enrichment-only changes adds useful semantic precision, though it does not explicitly differentiate the tool from sibling tools like search_exclusions or exclusion_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?

The description gives clear context for when to use the tool: when comparing two retained snapshots. It does not mention alternatives or exclusionary conditions, so it falls short of a 5, but the context is unambiguous enough for an agent to identify the intended use.

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