search-compendium-creatures

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It discloses that CR/type/size check real system data rather than name heuristics, that hasSpells/hasLegendaryActions are approximate index flags, that results are premium-first ranked, and that the tool returns minimal hits rather than full stat blocks. It also notes high result limits for complete encounter-building surveys. This is substantial behavioral context beyond what the schema provides, though it doesn't cover every edge case like error behavior or exact ranking algorithm.

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?

The description is dense but well-organized: it front-loads the core purpose and scope, then covers data source behavior, return format, and routing. Every sentence earns its place, though the parenthetical design.md reference and the slightly long final sentence could be trimmed. It's appropriately sized for a tool with six parameters and no annotations.

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?

For a discovery tool with no output schema, the description covers the key things an agent needs: what it searches, what it excludes, how the filters behave, what the return shape is, and how to follow up for full stat blocks. The main gap is that it doesn't describe pagination or what happens when no results are found, but the high result limits and minimal-hit return format are disclosed. Given the tool's complexity and the absence of annotations, this is nearly 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 100%, so the schema already documents all six parameters. The description adds context about the faceted criteria (CR, type, size, spellcasting, legendary actions) and clarifies that hasSpells/hasLegendaryActions are approximate flags, which adds meaning beyond the schema. However, it doesn't add syntax details for the parameters beyond what the schema already provides, so the baseline 3 is appropriate.

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?

The description opens with a specific verb and resource ('find creatures matching faceted criteria') and immediately distinguishes itself from sibling search tools by scoping to premium book Actor packs only, explicitly excluding SRD packs. It also names the companion tool get-compendium-entry for pulling full stat blocks, which clarifies its role as a discovery/identification tool rather than a retrieval tool.

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?

The description explicitly states when to use this tool (discovery across premium Actor packs) and when not to (SRD packs are excluded and never appear). It also provides routing guidance: use this to identify candidates by name, then use get-compendium-entry for full stat blocks. This is explicit when/when-not guidance with a named alternative.

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