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

No annotations are provided, so the description carries the full burden. It discloses the shape of the returned timeline, which is genuinely useful, but never states that this is a read-only operation, how far back history is retained, or whether history is trimmed by retention policies — meaningful gaps for a history tool.

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, zero waste: the return payload is front-loaded and the usage hint follows. Nothing repeats the name or title.

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?

With no output schema, the description usefully enumerates the returned fields, so an agent knows what it will get back. The remaining gap is behavioral rather than structural: retention scope and read-only nature are unstated for a tool with no annotations to cover them.

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 description coverage is 100%, so both `id` and `limit` (with its default of 20) are already documented in the schema. The description adds no meaning beyond that — no ordering direction, no pagination cursor behavior, no note on which snapshots count as 'changes'.

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?

States a specific verb and resource ('List a watch's snapshot timeline') and enumerates the returned fields (timestamps, content hashes, HTTP status, change flags), which clearly distinguishes it from mutation siblings watch_create/watch_delete. It does not explicitly name watch_diff or watch_check as alternatives, so an agent must infer the boundary from the field list.

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?

'Use to see how often a page actually changes' gives an implied usage context, but there is no explicit when-to-use versus watch_diff (compare snapshots) or watch_check (trigger a check now). Exclusions and prerequisites are absent, leaving routing between the four watch_* siblings to inference.

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