validate_facturx

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

With no annotations, the description fully discloses behavior: returns is_valid, errors, warnings with specific fields; requires optional saxonche extra; explains missing dependency behavior (unavailable instead of error); and notes limitations of EXTENDED-CTC-FR profile.

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 thorough but not overly verbose; each sentence adds value. It is well-structured, front-loading purpose, then scope, usage, and dependencies. Slight room for conciseness but overall effective.

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?

Given the tool's moderate complexity and presence of output schema, the description covers input, output, error handling, dependencies, and limitations comprehensively. No gaps remain for an agent to misuse.

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 coverage is 100%, but description adds critical context: for 'profile', it explains EXTENDED-CTC-FR limitation; for 'xml_content', it clarifies it is the embedded XML, not the PDF/A-3. These details enhance understanding beyond schema.

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 it validates Factur-X CII XML against Schematron rules, specifying scope (business-rule only) and distinguishing from XSD validation. It uses specific verb 'validate' and resource 'Factur-X CII XML document'.

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 suggests using this before embedding XML into PDF/A-3 or submitting via submit_flow, and notes that it is only for Schematron validation, not XSD. However, it does not explicitly compare with siblings like validate_ereporting_xml.

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