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

Annotations already declare readOnly/idempotent/non-destructive, but the description adds substantial context they don't cover: the extra LLM call cost, the exact success payload shape, the full enumeration of refusal_reason values, and the refusal_cause sub-classification for llm_error. This is behavior an agent must plan around (refusals are a normal outcome, not an exception).

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 the core differentiator and the routing behavior before the payload detail; nearly every clause is functional. The refusal_cause parenthetical is dense and slightly over-detailed relative to how often an agent will need it, which keeps it just below a 5.

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?

There is no output schema, so the description carries the full burden of explaining returns — and it does, specifying both the success object and every refusal variant. Combined with the cost note and the alternative-tool routing, an agent has everything needed to call and interpret it.

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 says nothing about prefer_tool (its override/routing semantics) or the alias set beyond the schema's own text, so it adds no meaning beyond structured fields.

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 ("extracts the answer using ONLY what the tool result contains") and explicitly contrasts itself with the sibling ask_pipeworx via "same routing ... then EXTRACTS". An agent can distinguish this from ask_pipeworx and ask_pipeworx_beta without opening any 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?

Gives an explicit when-to-use rule ("whenever an answer will be quoted, cited, or acted on, and the agent must not invent facts") with concrete examples, plus an explicit when-not/alternative ("prefer ask_pipeworx for casual lookups") and the cost tradeoff that motivates the choice.

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