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

With annotations already declaring readOnlyHint, openWorldHint, idempotentHint, and non-destructive, the description adds substantial behavioral detail beyond structured fields. It discloses the technical implementation: 'BGE-base-en embeddings + cosine over 500-char overlapping windows; cap is 200K chars (longer inputs are truncated and flagged).' It also highlights the value of character offsets for verification, which is useful for an agent deciding when to trust results.

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 appropriately sized at about 100 words, front-loaded with the core function, then usage context, then technical details. Every sentence contributes value: it states purpose, gives a when-to-use, names a sibling, and describes the embedding/truncation behavior. There is no filler or redundancy.

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?

Since there is no output schema, the description explains the return format: 'top-N passages with character offsets and similarity scores' and 'every passage carries an offset so the agent can verify a verbatim quote.' It also covers edge-case behavior with truncation, which is critical for long inputs. The explanation is sufficient for an agent to understand what results look like and how to use them.

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 baseline is 3. The description does not add new parameter semantics beyond what the schema already provides; it repeats the 'max ~200K chars' and includes example queries that are already in the schema. No additional clarification about parameter types, constraints, or interactions is given.

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 clearly states a specific verb and resource: 'Semantic search INSIDE a fetched record' and explains exactly what it does: 'Pass the text you already pulled ... plus a natural-language query; get back the top-N passages with character offsets and similarity scores.' It distinguishes itself from siblings by explicitly referencing 'ask_pipeworx_grounded' as a companion tool, and the context of 'too big to cram into the prompt' differentiates it from other query tools.

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 provides explicit usage context: 'Use when the record is too big to cram into the prompt — search_within saves context, returns only the passages that matter.' It also states the alternative path: 'Pairs with ask_pipeworx_grounded: fetch with the gateway, ground over the relevant passages instead of the whole document.' This clearly tells the agent when to use it and how it relates to a sibling tool.

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