Citation Generator API: DOI to APA, MLA, Chicago & BibTeX

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

Annotations only cover the read-only/open-world profile; the description adds substantial context beyond that: price ($0.003 per formatted citation), what is not billed (unresolved items, empty runs), a per-call spending cap via run_max_charge_usd, expected latency, and that bibliography files are written to the run's Apify key-value store rather than returned inline. It also discloses the minMatchScore resolution rule (exact for DOIs/IDs, fuzzy for text).

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?

Structure is excellent — purpose, differentiation, cost, latency, return shape — and the routing guidance is front-loaded. There is some avoidable repetition: 'Only formatted citations are billed' appears twice, and 'all styles are one price' duplicates the styles field text, which costs it the top score.

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 14-parameter, zero-required-parameter actor wrapper with no output schema, the description is thorough: it describes the return envelope ({actor, count, items}), lists per-item fields, notes truncation behaviour and structuredContent, and covers pricing, caps, and timeouts. An agent has everything needed to size, budget, and interpret a call.

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; the description earns extra by explaining cross-parameter interaction that the schema only hints at — run_max_items also limits what is billed and 'fills maxReferences when you leave it unset, so setting maxReferences higher can bill more than is returned'. It also states run_timeout_secs should be raised after timeout errors. Minor gap: it does not restate what minMatchScore or listUnresolvedInFiles do beyond the field docs.

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 opening sentence names a specific verb (Convert) and enumerates the accepted inputs (DOIs, ISBNs, PMIDs, arXiv IDs, titles, messy strings) and outputs (APA 7, MLA 9, Chicago, Harvard, IEEE, Vancouver, BibTeX, RIS). It explicitly distinguishes itself from reference_checker ('formats rather than audits') and literature_search, so an agent can route correctly without opening 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?

It gives positive triggers ('Use when you need a clean bibliography or .bib/.ris export') and explicit exclusions with named alternatives ('Do not use to find papers (use literature_search) or to prove references are genuine (use reference_checker first)'). It also advises on call batching (request every style in one call) and on timeout recovery.

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