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

Annotations already declare readOnly/idempotent/closed-world, so the safety profile is covered. The description adds genuine behavioral context beyond them: large numbers preserve digits, errors carry line and column, and TOML rejects null and non-table roots. These are real gotchas an agent would otherwise discover only by hitting them.

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?

Four short sentences, format scope front-loaded, each one carrying distinct information (scope, detection, numeric precision, error shape, TOML constraint). No filler or restatement of the title.

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 an output schema present, return values need not be described, and the description covers inputs, detection, and error/edge behavior. Minor gap: no mention of any size limits or hints on choosing a target format, but nothing essential for correct invocation is missing.

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 only 33% (only `text` is documented), but both `to` and `from` are enums with defaults that the schema already enumerates. The description adds that source detection is automatic, matching the `from: auto` default, and nothing about `to` beyond the format list. Adequate but not compensating for the coverage gap.

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 ("Convert") plus the exact resource formats (JSON, YAML, TOML, XML), which implicitly separates it from siblings like format_json (formatting only) and convert_csv_json (CSV involved). An agent can route to it without opening the 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?

The description supplies "Auto-detects the source," which hints that the `from` parameter can be left alone, but it never states when to choose this over format_json or validate_json_schema. Usage is implied through the behavior, not explained.

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