Wayback Lookup

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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive behavior. The description adds critical behavioral details: the meaning of 'status' values, that 'total_snapshots' is omitted when unavailable (not zero), error code mapping to warnings, and heavy domain fallback. No contradiction with 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?

The description is moderately long but highly informative, front-loading the purpose and then providing usage guidelines and behavioral caveats. Every sentence adds value, though it could be slightly more concise.

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?

Given the tool's complexity (one parameter, rich output, error handling, rate limits, alternative tool), the description covers return value structure, status meanings, error codes, and usage context. The presence of an output schema (though not detailed here) is noted, and the description provides sufficient context for an agent to select and use the tool correctly.

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 single parameter 'domain' has 100% schema coverage with a clear description. The tool description does not add new semantic details beyond the schema, so a baseline score of 3 is appropriate.

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 retrieves Wayback Machine snapshots for a domain, specifying what is returned (first capture, latest, total count, snapshot list). It distinguishes from the sibling tool 'domain_report' by mentioning 'for full audit use domain_report'.

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?

Explicitly states when to use this tool ('investigate domain history and age') and provides an alternative ('for full audit use domain_report'). Also includes rate limits and warnings about heavy domains, guiding proper invocation.

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