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

Annotations already cover the safety profile (readOnly, idempotent, openWorld, non-destructive), so the bar is lower, and the description still adds non-obvious behavior: the implicit has_eval=true fallback and the fact that filters compose. It does not mention pagination or result ordering, but for a boolean-filter listing that is a minor omission.

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?

Three tight sentences: what it lists, how the filters behave, then what comes back. The most important detail, the implicit has_eval=true default, is not buried. No filler.

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?

An output schema exists, so the brief return-field summary is a bonus rather than a requirement. Combined with annotations and the default-filter disclosure, an agent has enough to call this correctly; only the unspecified limit parameter keeps it from being fully complete.

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 0%, so the description bears the full burden, and it mostly carries it: it names the five boolean filters and explains that false is a meaningful negative selection rather than an omission. Only 'limit' is left unexplained, and the null-vs-boolean default behavior is inferred rather than stated.

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 scanned JavaScript files that match code-pattern filters') and enumerates the five filter dimensions, so the agent knows exactly what corpus and selection mode this covers. It never names a sibling, though, so an agent must infer the split against the many search_js_fingerprint_by_* hash/library tools on its own.

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 real selection semantics: false selects files *without* the pattern, filters can be combined, and with no filter has_eval=true is applied by default. That default is exactly the kind of guidance agents need. It stops short of saying when to prefer this tool over hash-based or library-based sibling searches.

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