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

Annotations already cover the safety profile, and the description still adds substantive behavior: filter combination rules (AND across fields, OR within arrays), inclusive ranges, exclusion of documents lacking a filtered field, response shape (total/hasMore, {name, uuid}), sort order (level then name), and a bridge version requirement (8.11.0+). That is well beyond what annotations or schema disclose.

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 purpose, then clearly labeled format rules, filter behavior, response contract and an example — easy to scan. A little padding is spent restating schema facts (ALL-OF traits vs ANY-OF traditions, level = spell rank), which are already in the parameter descriptions.

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 11 parameters, nested objects and no output schema, the description carries the return-value burden itself, and it does: total/hasMore, {name, uuid}, level field and sort order. Combined with the version prerequisite and format caveats, an agent has everything needed to call it correctly.

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 coverage is 100%, so the baseline is 3. The description adds real semantics the schema lacks, notably 'priceGold is per batch for batched goods like arrows' and a worked example payload showing nested range syntax. The traits/traditions and level-as-spell-rank restatements duplicate existing schema text, limiting the gain.

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+resource+scope: 'Search COMPENDIUM packs for items with Pathfinder 2e structured filters (pf2e worlds only)' and enumerates the covered item types. This clearly separates it from compendium-search, world-item-filter, pf2e-compendium-filter-actors and the dnd5e variant named in the sibling 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?

Gives an explicit environment constraint ('pf2e worlds only') and routes the agent onward: 'uuid-resolve, or compendium-browse with ids to batch-load'. It does not say when to prefer this over compendium-search/page-search for a plain keyword lookup, so the when-not half of the guidance is missing.

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