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

With no annotations, the description must carry the full behavioral burden. It usefully discloses that this is a paid operation costing £0.49 and that it returns a Stripe Checkout URL rather than the data itself, but leaves unclear whether a checkout session is created, what happens after payment, and what 'Soft-Offer outbound is OFF' actually means.

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?

Very compact and front-loaded with the core purpose and return type. The trailing fragment 'Soft-Offer outbound is OFF' is cryptic and costs some clarity, but the overall definition is efficient rather than bloated.

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 paid, transactional tool with no output schema and no annotations, this covers the essentials (price, what is returned, what the pack contains) but omits the post-checkout flow and any link to 'redeem_pack', leaving an agent without the full picture of how the purchase completes.

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 both 'query' and 'size' (default 25, max 100) are already documented in the schema. The description adds no parameter meaning beyond the schema, making 3 the correct baseline.

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 resource ('tender-score pack') and what it contains (notices, fit_score/fit_flags, risk_flags), plus that it returns a Stripe Checkout URL. This is clearer than a bare name restatement, but it never distinguishes it from the sibling 'tenders_pack' or explains what 'score' adds relative to that alternative.

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 description implies a paid purchase flow but gives no explicit when-to-use guidance, no prerequisites, and no routing versus siblings like 'redeem_pack' or 'tenders_pack'. An agent must guess whether this initiates a purchase or is the follow-up step after redemption.

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