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

With zero annotations the description carries the full burden and does so unusually well: hard limits (10 MB, 1M cells), a stated price (€0.006 per file), the auth mechanism (API key in Authorization: Bearer), and the exact auto-detection rules for delimiter, encoding and source format. It also discloses that schema_only produces no output file, which is precisely the kind of side-effect an agent needs before calling a paid mutation-ish tool.

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-loaded with capability, then detection rules, then limits/cost, then a compact parameter list — a sensible priority order with no filler sentences. The trailing 'Parameters —' block restates schema property names, which is mildly redundant, but each entry adds meaning the 0%-coverage schema does not.

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?

An output schema exists, so return values need no explanation; the description instead covers what an agent cannot infer — cost, size ceilings, auth, detection order, and the no-file schema_only mode. For a 7-parameter, 0%-schema-coverage, unannotated conversion tool, the only remaining gap is the from/source naming mismatch.

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 description coverage is 0%, so the description must compensate, and it documents all seven parameters including the format enums for source/to and the xlsx sheet selector. One flaw: it refers to 'from' being omitted while the actual parameter is named source, and the schema types schema_only as a string while the description says bool — both create avoidable ambiguity for the caller.

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?

Names a specific verb (convert) plus the exact resource set — csv, tsv, json, ndjson, xlsx, parquet — with directionality ('between'). That enumeration alone separates it from doc_convert, md_convert and table_extract in the sibling list, since none of those claim this tabular format matrix.

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?

Usage context is implied rather than stated: auto-detection from the file signature when source is omitted, and a schema_only path for inspecting column names/types without producing a file. There is no explicit when-to-use-this-vs-sibling guidance, e.g. no pointer telling the agent to prefer table_extract for pulling tables out of a PDF or doc_convert for document formats.

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