invariance_receipt_create

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

Beyond the annotations, the description adds valuable behavioral context: the operation requires an AGENT API key, operator tokens are rejected with 403, and the receipt records proof of an external action. This meaningfully supplements the write implication already present in readOnlyHint=false. No contradiction with annotations exists.

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 two sentences with no filler. The core purpose is stated first, followed immediately by the critical authentication constraint. Every sentence 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 single-parameter creation tool, the description plus schema provide enough to call it correctly: purpose, auth requirements, and full parameter details. It lacks guidance about the sibling receipt_batch tool and does not describe the response shape, but those are minor given the schema's completeness and the tool's simplicity.

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 the schema itself fully documents the receipt parameter with required fields, optional fields, allowed source values, and an example. The tool description adds no additional parameter semantics. This meets the baseline for fully-covered schema parameters.

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 clearly states the verb and resource: 'Record one external receipt (proof an external action happened)'. However, it does not explicitly distinguish this from sibling tools like invariance_receipt_batch, invariance_receipt_list, or invariance_receipt_get, beyond the word 'one'.

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 conveys the intended use case: recording a single external receipt as proof of an external action. It also provides a usable constraint by requiring an AGENT API key and explicitly noting operator tokens receive 403. It does not, however, mention alternatives such as receipt_batch for bulk recording or receipt_list/get for retrieval.

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