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

No annotations are provided, so the description carries the full transparency burden. It discloses the signed Ed25519/RFC 8785 format, byte-reproducibility, no-LLM guarantee, source/retrieval time, the 75-reference limit, the $3.00 payment, unpaid-call isError behavior, result fields, and the client-side spend-cap failure mode.

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 dense but every sentence carries operational information: what is verified, input formats, output properties, payment details, failure modes, and correct sibling routing. The payment/spend-cap warning is essential and not extraneous.

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?

Despite lacking an output schema, the description covers the return content, payment semantics, and usage boundaries well. The main remaining gap is the undocumented meaning of strict_authors and include_unpaywall, which an agent may need to set correctly.

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 67%, with options (strict_authors, include_unpaywall) and several reference subfields lacking descriptions. The description adds only 'structured references or BibTeX' and the 75-reference cap, which is helpful but does not explain the option flags or subfield semantics. It also introduces a potential conflict by saying 'Up to 75 references' while the schema allows maxItems: 200.

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 states a specific action ('Verify a bibliography') and enumerates the exact checks performed, so an agent immediately knows the tool's purpose. It also explicitly routes evidence-finding queries to evidence_pack_preview/evidence_pack, but it does not differentiate itself from the sibling citation_report or citation_report_preview beyond the title's 'large tier' label.

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 explicit guidance: use this tool when you 'already have' references to check, and use evidence_pack_preview/evidence_pack instead when finding papers for a question. It also warns about the x402 spend cap and how to handle it, which is actionable usage guidance.

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