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

Annotations already establish readOnly, idempotent and closed-world behavior, so the bar is lower, yet the description adds real value: what the response contains (payback in months, asking multiple vs comparables, fired flags with severity and rule links, seller questions) and a key behavioral limitation (no URL fetching). It does not mention rate limits or the listing-size ceiling, which is documented only in the schema.

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 tight sentences, front-loaded with what the tool does, followed by inputs, outputs and scope limits. Every sentence carries distinct information with no repetition of the schema.

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?

With no output schema, the description compensates by enumerating the return payload, and it covers scope, accepted inputs, sources and explicit non-goals. An agent has everything needed to decide to call it and to interpret the result.

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 seven parameters are already well documented and the baseline is 3. The description adds only a light nuance — that listing text and/or the key numbers may be supplied — without explaining any individual parameter beyond what the schema states.

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 ('Runs FirstPass Memo's 33 published red-flag rules on a small online-business listing') plus the exact market segment, price band and sources it targets. This clearly distinguishes it from the sibling list_rules, which only enumerates rules rather than applying them.

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 clear context for use ('Pass the listing text the user provides and/or the key numbers') and explicit exclusions ('Screening only: not advice, a valuation or verification'). It also rules out a plausible misuse ('Does not fetch URLs'), though it never explicitly names list_rules as the alternative for inspecting the rules themselves.

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