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

Annotations already declare this as a safe, closed-world read, so the description is free to add the genuinely new facts: per-call pricing ($0.005 USDC via x402, client-paid) and that failed calls are not billed. That cost/billing disclosure is real context an agent cannot get from structured fields. What it does not disclose is what a successful response looks like (a list of chunks, with offsets?).

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?

Front-loaded with purpose, then strategy semantics, then cost. The sentence declaring it 'the highest-value endpoint for agents that build retrieval pipelines' is filler and could be cut without losing information.

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?

No output schema exists, so the description must carry return semantics, and it does not say what comes back (chunk array, boundaries, offsets). Combined with a zero-parameter schema that the description implicitly contradicts by discussing strategies, an agent has an incomplete picture of how to drive and consume this tool.

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?

Parameter count is 0, which normally sets a baseline of 4. However, the description describes three 'strategies' (sentence, paragraph, fixed) as if they were selectable inputs, while the schema declares an empty object with no such fields. That mismatch muddies rather than clarifies how the caller controls behavior, so it lands below baseline.

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?

States a specific verb and resource ('Split long text into pieces for RAG retrieval') and immediately scopes it to a use case, which cleanly separates it from normalize, hash, dedupe and the other text utilities in the sibling list.

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 RAG-pipeline framing implies when to reach for this tool, but there is no explicit when-not guidance or named alternative (e.g. versus normalize or extract). The line 'highest-value endpoint for agents that build retrieval pipelines' is promotional rather than routing guidance.

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