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

Goes well beyond the readOnly/idempotent/destructive annotations by revealing the underlying mechanism (BGE-base-en embeddings + cosine over 500-char overlapping windows), the 200K-char cap with truncation-and-flag behavior, and the output structure (passages with offsets and similarity scores). This gives the agent a robust mental model.

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?

Four dense sentences, each serving a distinct purpose: core action, use case, sibling pairing, and technical edge-case behavior. Front-loaded with the most critical information and no filler.

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 must explain return values, and it does: 'top-N passages with character offsets and similarity scores.' It also covers the oversized-input truncation behavior. For a 3-parameter tool, this is fully self-contained.

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 100%, so the baseline is 3. The description adds value by providing realistic examples for 'text' (SEC 10-K body, article, long tool result) and clarifying the truncation edge case for the 'text' parameter. It also gives a concrete query example, slightly exceeding the schema's own descriptions.

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 'Semantic search INSIDE a fetched record', clearly stating a specific verb+resource and distinguishing it from siblings. It explicitly contrasts with ask_pipeworx_grounded, framing search_within as a passage-level retrieval tool versus whole-document grounding.

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?

Provides explicit when-to-use guidance: 'Use when the record is too big to cram into the prompt' and explains the benefit (saves context). Also details a concrete workflow pairing with ask_pipeworx_grounded, making the usage context actionable.

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