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

With no annotations, the description carries the full burden, and it does add real value by disclosing the auth/payment profile ('does not require a bearer key or payment') and that the underlying series is immutable, implying a safe read. It omits failure behavior (unknown ID, unpublished series) and the shape of what comes back, which matters for an unannotated tool.

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?

Two tight sentences: the core operation first, then the auth/payment caveat. Nothing is padded and nothing is buried.

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?

For a two-param tool with no annotations, no output schema, and no schema descriptions, the description does less than it could: the merchantId requirement and the return shape (presumably a full offer object) are undocumented. Adequate to invoke on the happy path, but an agent would be guessing at the response and at the merchantId role.

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 0% — the schema supplies only UUID formats, no semantics. The description explains offerId implicitly ('any known offer ID') but never mentions merchantId at all, despite it being a required parameter, and doesn't clarify why both are needed or how they relate.

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 ('resolve') and a precise transformation: any known offer ID → the currently published latest version within its immutable series. The concept of an immutable offer series with versions is clearly communicated. It doesn't explicitly name or differentiate from the closest sibling, discover_merchant_offers, so it falls short of a 5.

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?

'Resolve any known offer ID' implies the precondition (you already hold an offer ID in hand), which is a reasonable usage cue. However, it never states when to prefer discover_merchant_offers instead, nor what happens when the ID is unknown or has no published version — the exclusions are left to inference.

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