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

Beyond annotations, the description discloses concrete behaviors: returns top-N passages with character offsets and similarity scores, uses BGE-base-en embeddings with cosine similarity over 500-char overlapping windows, and has a 200K character cap with truncation flagging. This contextualizes the read-only nature and adds useful operational details.

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 sentences, front-loaded with purpose, then use case, then technical details. Every sentence earns its place: no filler, no repetition of schema fields. The size is appropriate for the tool's complexity.

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?

The description covers the input (text, query), the output (passages with offsets and scores), the algorithm, the limits (cap and truncation), and the relationship to a sibling tool. Without an output schema, it still explains return values sufficiently. No significant gaps.

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 adds contextual meaning by telling the agent to pass text already pulled (with examples like SEC 10-K body) and describes query as natural language. It also mentions 'top-N passages' which relates to limit, but the schema already covers parameter ranges and defaults. The extra context earns a 4.

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 an explicit verb+resource: 'Semantic search INSIDE a fetched record.' It clearly distinguishes from siblings by specifying that search_within operates on already-pulled text, and the pairing with ask_pipeworx_grounded highlights the boundary. This is a specific, differentiated purpose.

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 direct usage guidance: 'Use when the record is too big to cram into the prompt' and explicitly contrasts with ask_pipeworx_grounded, saying to fetch with the gateway and ground over relevant passages instead of the whole document. This gives the agent a clear decision rule and names the alternative.

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