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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds valuable behavioral context beyond those hints: it is advisory-only, does not execute payment, does not access a wallet, and returns one of three triage labels. No contradiction with annotations.

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?

The description is a single compact sentence with no filler. It front-loads the core behavior (what it returns) and then adds the critical safety qualifier (advisory, no payment/wallet access). Every clause earns its place.

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 6-parameter decision tool with no output schema, the description states the return categories and assures no side effects. The parameter names and enums are mostly self-explanatory, and the closed-world/read-only annotations cover safety. It stops short of explaining the mapping of inputs to outputs, but that is plausibly intentional since the mandate is owner-defined.

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 only 17% (only mandateValid has a description). The description references the mandate concept but does not explain the meaning of vendorStatus, receiptStatus, amount, perRequestLimit, or dailyRemaining, nor how they combine to produce a decision. With such low schema coverage, the description needed to compensate and largely does not.

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?

The description opens with a specific verb and result—'Return eligible, escalate, or block'—and identifies the resource as an agent spend request under an owner-defined mandate. It also disambiguates the tool's nature with 'Advisory preflight only', making its role unmistakable even with no sibling tools to differentiate.

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?

There are no sibling tools, so no alternative routing is needed. The description gives clear usage context: this is a preflight evaluation tool. It also provides an explicit when-not boundary with 'never executes payment or accesses a wallet', which helps an agent avoid misuse. A 5 would require an explicit 'use when' statement or explicit alternative names.

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