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

With no annotations, the description carries the full burden. It implies a read-only operation via 'Check', but it does not disclose that the npub parameter is for credit billing (and thus the call likely consumes credits), nor that a DPoP token is involved. No mention of side effects, rate limits, or response behavior is made.

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 short, front-loaded sentence with no fluff. It conveys the essential operation and the two primary call variants efficiently.

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?

The description is too sparse for a tool with no annotations. It lacks the critical detail that npub is required for billing, and the schema itself contradicts this by marking no parameters as required. The dpop_token field is left unexplained, and with many sibling check/list tools, more context about stock semantics and invocation prerequisites would be needed for reliable agent use.

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?

The description adds meaning to the sku parameter by tying it to 'one SKU' versus 'whole stock list', which complements the schema's 'Omit to get the full stock list'. However, the dpop_token parameter has no schema description and no description-level explanation, and the npub billing context only appears in the schema, not the tool description. With 67% schema coverage, the description partially compensates but leaves a gap.

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 names a specific verb ('Check'), a specific resource ('Roastify stock'), and the two operation modes ('one SKU, or the whole stock list'). This clearly distinguishes the tool from sibling check tools like check_price or check_balance, though it doesn't elaborate on what 'stock' means exactly.

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?

No guidance is given on when to prefer this tool over alternatives such as roastify_browse_catalog, roastify_get_catalog_product, or roastify_check_price. The description only distinguishes two modes (single SKU vs. full list), not the contextual scenarios that would select this tool.

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