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

Annotations already mark the tool as read-only and non-destructive, lowering the bar. The description adds useful behavioral context beyond annotations: it returns passages with source links and explicitly states 'Fast; no model call,' which helps an agent set expectations about latency and behavior. No contradiction with annotations.

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?

Two efficient sentences with no filler. The core action and result are front-loaded, and the parenthetical scope list adds useful specificity without bloat.

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 search tool with a read-only annotation, a simple schema, and no output schema, the description adequately conveys what the tool returns and the knowledge domain covered. It could be more complete by explicitly distinguishing itself from ask_henry, but the core calling context is covered.

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 67%: limit and session already have descriptions, while query has only length constraints. The description does not add meaning for the query parameter beyond the general knowledge-base scope, but this is acceptable because most parameters are already documented in 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?

The description states a specific verb and resource: 'Search HenryKnows' knowledge base' and lists the covered content areas. It clearly conveys that the tool returns matching passages with source links for citation. It does not explicitly name or contrast the sibling tools, though 'no model call' hints at a difference from ask_henry.

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 gives clear context: use this when you need retrievable passages and source links to read and cite yourself, and it notes the tool is fast and does not make a model call. It does not provide explicit when-not-to-use guidance or name alternatives, but the intended use case is implied strongly enough.

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