check_availability

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

The description indicates a read-only operation (checking and returning) but does not elaborate on edge cases (e.g., what happens if no snapshot exists, or how 'closest' is determined). Since no annotations are present, the description carries the full burden of behavioral disclosure but falls short of being fully transparent.

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 sentence of 15 words, efficiently conveying the core purpose without any filler. It is front-loaded with the action ('Check if a URL has been archived') and immediately states the return value.

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 no output schema, the description should hint at the return structure (e.g., snapshot metadata) and possible error cases. It only says 'return the closest snapshot', which is vague. For a simple tool this is adequate but not fully informative for 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?

With 0% schema description coverage, the description must compensate. It clarifies that 'url' is the URL to check and that 'timestamp' is optional but does not explain its role (e.g., that it is used to find the closest snapshot to that time). This leaves ambiguity about the timestamp parameter's meaning and usage.

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The description clearly states the verb 'Check if a URL has been archived' and the resource 'the Wayback Machine', with the outcome 'return the closest snapshot'. This differentiates it from siblings like lookup_snapshots (which would return multiple snapshots) and get_snapshot_content (which retrieves a specific snapshot's content).

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 the tool is for checking availability of a URL, but it does not explicitly say when to use it versus siblings like lookup_snapshots or search_archive. No when-not or alternative guidance is provided, so an agent may not know the best tool for different scenarios.

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