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

With no annotations, the description carries the behavioral burden and does disclose the return shape ('valid/invalid with every failed rule: id, severity, message, XPath') and that it delegates to external official rule sets per format. It does not state permission/auth needs, network or runtime characteristics, or that it is strictly non-mutating, so it stops short of full disclosure.

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?

Two sentences, with the core action and return contract front-loaded. The parenthetical format/rule-set mapping is long but information-dense and non-redundant, so it earns its space; only minor tightening is possible.

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?

Covers the rule-set matrix and the failure-report shape well for a tool with no output schema and no annotations. It is incomplete on the practical contract, though: required=0 while one of content/content_base64 must actually be supplied, and the detect_invoice prerequisite is only implied rather than stated.

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 all three parameters (kosit, content, content_base64) are already documented in the schema, which sets the baseline at 3. The description adds no syntax or format detail beyond the schema for kosit, content, or content_base64, and notably omits that one of the two content inputs is effectively required despite required=0.

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 ('Run the official rule set for the detected format') and enumerates exactly which rule set applies per format (KoSIT, OpenPeppol, FA(3), HR-CIUS, Facturae, LHDN). This clearly separates it from sibling tools like detect_invoice, parse_invoice, and fix_invoice without needing to open any schema.

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 phrase 'for the detected format' implies a detect_invoice step must precede this call, which is useful implied sequencing. However, it never explicitly says when to choose this over fix_invoice or parse_invoice, and names no exclusions or prerequisites for the content inputs.

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