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

Annotations only declare the safety profile (readOnly=false, destructive=false, openWorld=true), so the description carries the rest — and it delivers: credit consumption, per-request vs per-page billing, cost from extra configuration components, where pricing lives, the EUR 25 starting credit, and hard timeouts on download and page count. This is unusually rich behavioral disclosure beyond structured fields.

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?

Front-loads the most decision-relevant fact ('SPENDS CREDITS') and stays to a single paragraph with no filler. The billing sentence is dense with nested parentheticals, which slightly hurts scannability, but every clause carries information.

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 7-parameter, zero-required, no-output-schema tool, the description covers cost, input modes, timeouts and the return shape (JSON key-values and tables). It does not mention the async capture path for large/long-running documents despite 50-page timeouts, which is the main remaining gap.

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%, so the baseline is 3, but the description adds a genuine constraint the schema lacks: url, data_base64 and file_id are mutually exclusive ('exactly one of'), and the schema declares zero required parameters with no oneOf. That is real value over the 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?

States a specific verb+resource: 'turn any document into generic structured data: key-value pairs and tables, as JSON'. The word 'generic' implicitly contrasts with the specialized capture siblings (bank_statement, einvoice, salary_slip), but no sibling is named explicitly, so an agent must infer the routing rather than read it.

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?

Gives clear guidance on input selection ('Give the document as exactly one of url, data_base64 or file_id') including size-based preference elsewhere in the schema, which is useful routing. However, it never says when to pick this generic capture over dochorizon_capture_bank_statement, capture_with_prompt or the async alternative — that choice is left implicit.

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