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

Annotations already cover readOnly, idempotent, non-destructive and closed-world, so the safety profile is handled. The description adds genuinely non-schema information: it is free (cost), it is the prerequisite step for slug acquisition, and it carries a usage policy constraining lawful purposes. The policy is valuable context an agent cannot infer, though the return-format details are partly redundant with the output schema.

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 operative content is front-loaded in two efficient sentences ('Call this first to get a slug. Free.'). The three-sentence prohibition block is long relative to the functional payload and could be condensed, but it is policy text rather than filler.

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?

All three optional filters are documented in the schema, annotations are complete, and an output schema exists so return values need no further explanation. Nothing an agent needs to call this correctly 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 description coverage is 100% and two of three params are enums, so the schema already fully documents filtering. The description's 'Filter by category, kind or a query on the name or slug' restates the schema without adding format or edge-case guidance; 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 ('List the receipt templates') and names the consuming sibling ('make_receipt can use'), plus enumerates the returned fields (slug, name, category, kind). An agent can immediately distinguish this discovery tool from make_receipt and the other siblings.

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?

'Call this first to get a slug' gives an explicit ordering constraint relative to make_receipt, which is the only real alternative an agent would consider. It also names the three filter axes, so the agent knows exactly how to narrow results.

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