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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint=false and destructiveHint=false, so the safety profile is covered. The description adds real value beyond that by disclosing the return granularity ('titles + categories + one-line summaries, not full bodies') and reaffirming deterministic repeat behavior. It omits any result-count limit or pagination behavior, which keeps it short of a 5.

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-loads the trigger ('Use this when you need to find...') then layers scope, return shape, and the alternative in compact clauses. Three sentences, no filler, each carrying distinct information.

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 no output schema, the description correctly compensates by describing what comes back, and annotations handle the safety profile. The one remaining gap for a search tool is result limits or ordering, which an agent might need when a query is broad.

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% and both parameters are documented there, so the baseline is 3. The description's mention of title/summary/category describes matching fields rather than adding syntax or semantics for 'query' or 'category_path', so it does not meaningfully exceed the schema.

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 ('find existing Eigma pages') plus matching scope ('matches title, summary, category') and explicitly separates itself from eigma_read_page, which supplies full bodies. An agent can distinguish this search tool from its siblings without opening any 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?

Gives concrete when-to-use contexts ('to locate the page to update, or the page(s) that answer a question') and names eigma_read_page as the follow-up for full text. It does not, however, contrast with the other search-adjacent sibling eigma_browse_wiki or eigma_resolve_pages, so the routing is clear but not exhaustive.

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