Show the local cache location, schema and per-user coverage

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

Annotations already cover read-only/idempotent/no-open-world, so the bar is lower; the description still adds value by stating 'NO API call' (a meaningful behavioral distinction from API-backed siblings) and detailing exactly what is reported, including WAL size and resume offset of an unfinished backfill.

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?

Front-loaded with the key distinction (local, no API call) before the field list. The returned-field enumeration is dense but each item earns its place for a diagnostic tool; only marginally long.

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 fully carries the burden by enumerating every returned field, including coverage_complete, resume offset, and last_synced_at. An agent has everything needed to decide to call it and interpret the result.

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?

Zero parameters, so per the baseline this scores 4. The description correctly requires no parameter explanation and instead spends its words on return semantics.

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?

Specific verb+resource: diagnostics for the LOCAL check-in cache, explicitly contrasted with API-calling siblings via 'NO API call'. The enumeration of returned fields (path, size, journal mode, schema version, per-user coverage) makes the scope unambiguous and distinguishes it from query tools like untappd_cache_query.

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?

Gives concrete when-to-use guidance: 'confirm the cache persisted across restarts' or 'see how far a backfill has got.' Clear context, though it does not explicitly exclude alternatives or name which cache sibling to use instead when the goal is to read records rather than diagnose.

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