lookup

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

No annotations are provided, so the description carries the full burden. It discloses read-only behavior ('Read-only'), non-interactivity ('nothing here reaches you unprompted'), matching limits ('up to 25 matching lines'), and the shape of replies ('id, kind, text' plus counts). It doesn't explicitly discuss rate limits or failure modes, but the behavioral surface is unusually well disclosed for a search tool.

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 purposeful; nearly every clause earns its place and the critical scoping constraint and call-before-remember advice are front-loaded. It is a long paragraph, but the complexity of five invocation modes justifies the length. It could be slightly tightened, but there is no fluff.

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?

Given no output schema, the description covers what an agent needs: return shapes (catalogue, matches with id/kind/text, 'no matches'), limits, scope semantics, and exclusions (Lookup items are not queryable by free-text). The sibling context and missing output schema are fully compensated by the description's detail.

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 already 100%, but the description adds semantic interactions beyond the schema: 'key answers only a Lookup item's own exact key (query and scope are then ignored)' clarifies precedence, and the mode-by-mode breakdown (no args, scope alone, scope+query, query alone) explains what combination produces what result. This is meaningful added value over the schema alone.

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 strong verb-resource pair ('searches THOR's memory') and immediately distinguishes itself from a current-project-scoped search. It names the sibling 'search_code' implicitly by contrast ('never scoped to only the current project') and covers all invocation modes, so an agent knows exactly what this tool does.

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 says 'Call this before remember, so an existing near-duplicate becomes a revise instead,' which gives a concrete when-to-use instruction and a direct alternative ('remember', 'revise'). It also enumerates the parameter-mode conditions (no arguments, scope alone, scope+query, query alone, key alone), leaving no ambiguity about which input combination to choose.

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