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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so the safety profile is covered. The description adds real value beyond that: the results are pre-computed and cached, the listing is a lean one-entry-per-view overview, and the id is the handle into three differently-shaped access paths. It doesn't discuss visibility scoping rules, staleness of last_built, or pagination of the list itself.

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 purpose, then semantics, then routing, then the exclusion — a logical ordering with no filler. The enumeration of returned fields (id, name, description, last_built, access) is somewhat redundant given an output schema exists, costing a bit of space.

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?

Complete for a zero-param discovery tool: it explains what a view is, that results are cached, what the id unlocks across three sibling tools, and when to switch to collections. With an output schema present, it needn't detail return shapes further, and annotations carry the safety profile.

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 tool takes zero parameters, which is the baseline-4 case; there is nothing for the description to disambiguate. It correctly explains that all filtering is handled by downstream tools taking the returned id rather than by this call.

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?

Opens with a specific verb+resource ('Discover the pre-computed data views') and immediately defines the domain concept ('Twig-defined queries that aggregate across collections; result is cached and accessible by id'). It explicitly distinguishes itself from list_collections, so an agent can separate it from the many collection-oriented siblings without opening a schema.

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?

States exactly what to do next with the returned id and names each downstream tool with its role: query_view for paginated queries, get_view for the whole cached result, describe_view for shape/metadata. It also names the exclusion condition ('For raw collection content use list_collections instead'), which is a genuine when-not-to-use rule.

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