Validate a bank statement PDF (proof calculation)

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

Annotations already declare readOnlyHint=true, so the safety profile is covered; the description adds real behavioral context beyond that: the scope limit (only proof-calculation checks, not full validation), the supported document source (currently SumUp only, German statements), and the specific invariants checked. It stops short of saying what happens when a check fails or what the result looks like.

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, front-loaded with what is parsed and which checks run, with the use case trailing at the end. Every clause carries information (source, checks, invariants), though the first sentence is dense with parentheticals and slightly harder to scan than it needs to be.

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?

With no output schema, the description should ideally describe the validation result shape (pass/fail, which invariants failed), but it only states what is checked. Everything else an agent needs to call it correctly — read-only nature, single file path, supported source — is present.

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?

There is one parameter and schema coverage is 100%, so the schema already documents file_path fully. The description adds only indirect guidance by specifying this must be a German SumUp statement PDF, which constrains the accepted input, but no path, format, or size details beyond the schema. 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 pair (parses + runs proof-calculation checks) on a specific resource (German bank statement PDF, currently SumUp) and enumerates exactly which checks run: sums vs header totals (incoming, outgoing incl. fees, balance delta) and per-row running balance. This is far more precise than the sibling parse_bank_statement would need, so an agent can distinguish validation from plain parsing.

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?

It gives a clear use case: 'Use this to verify a statement was read completely and correctly,' and the 'only the proof-calculation checks' phrasing implies broader validation exists elsewhere. However, it never names parse_bank_statement or export_bank_statement_csv as the alternatives, so the routing decision is left partly to inference.

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