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

readOnlyHint=true is consistent with a fetch, and the description adds value beyond annotations by disclosing that the payload contains sensitive commission data plus a policy constraint on surfacing it to end users. It does not cover behavior on an invalid or stale offer_id, which keeps it from a 5.

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?

One sentence enumerating the return payload followed by a short constraint clause — no filler, and the highest-value information (what you get) is front-loaded before the caveat.

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 correctly compensates by listing the returned fields, and it flags the data-sensitivity constraint an agent needs before relaying results. Minor gaps remain around error behavior and whether language affects only the description field, but nothing essential to invoking the tool is missing.

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 offer_id, language and agent_key are already documented in the schema, including the ak_ format and the "never make one up" warning. The description only reinforces that offer_id originates from search_offers and adds no new meaning for the optional parameters, so baseline 3 applies.

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 ("Get the full terms of an offer") and enumerates exactly what is returned: description, countries, commission type and rate, cookie window, hold period. It also anchors the tool to its sibling by saying the offer comes from search_offers, so an agent can distinguish it from get_link/get_stats without opening a 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?

The phrase "returned by search_offers" establishes the required prerequisite call ordering, and "For your own planning — do not show commission details to end users" gives an explicit audience restriction. It stops short of naming a when-not case or a fallback tool, but for a detail-lookup tool the guidance is clear.

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