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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered by structured data. The description adds only the workflow context that this is a pre-write lookup and that results span two domains, but says nothing about result ordering, matching behavior beyond what the schema states, or cost/latency. Useful but thin against an already-complete annotation set.

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?

Three short sentences with no filler: scope first, then the motivating use case, then the routing alternative. Every sentence carries information the agent needs.

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?

An output schema exists, so return structure need not be explained, and the description covers scope, use case, and the nearest alternative. The only minor gap is that it does not hint at the two-list result shape or how a caller should treat partial matches, which matters for a search tool, but nothing essential for correct invocation is missing.

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 limit, query, and cursor semantics (literal case-insensitive matching, page size, cursor chaining) are already fully documented in the schema. The description adds no parameter-level meaning beyond that, so the baseline 3 applies.

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 names a specific verb (search) plus the two concrete resource domains it covers (trained question/answer pairs and ingested knowledge sources), and explicitly distinguishes itself from the sibling list_knowledge_sources. An agent can tell what this returns without opening the 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?

It states the exact decision context ('check whether an answer already exists before writing a new one', i.e. before add_trained_answer) and names the alternative tool with the condition that selects it ('to list all knowledge sources and their sync status, use list_knowledge_sources'). This is explicit when-to-use plus a named alternative.

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