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

No annotations are provided, so the description carries the full behavioral burden, and it discloses nothing: no indication of whether the SQL is executed, whether this is read-only, whether the underlying database is touched, or what permissions are required. For a tool whose name implies inspecting query internals, this silence is a serious gap.

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 short but only because it is empty — the same phrase repeated twice with a colon. This is under-specification rather than conciseness, and there is no front-loaded information to speak of.

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 annotations, no output schema, four undocumented optional parameters, and no sibling differentiation, the definition is completely inadequate for an agent to invoke this tool correctly or know what to expect back.

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 nominally 100%, but the schema text ("Sql to process", "Data to process", "Text to process", "Input to process") is itself vacuous placeholder text, and the description adds nothing. Four optional, indistinguishable string parameters are left entirely unexplained, so an agent cannot tell what `data`, `text`, or `input` are for versus `sql`.

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 is "SQL Explain: SQL Explain", a pure restatement of the tool name with no verb, resource, or scope added. An agent learns nothing about what "explain" produces (query plan? plain-language explanation?) or how it differs from sibling tools like x402-sql-check, x402-sql-validate, or x402-sql-format.

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?

There is no when-to-use guidance, no prerequisites, and no mention of alternatives despite several SQL-adjacent siblings in the catalog. Nothing indicates when an agent should pick this over x402-sql-format or x402-sql-validate.

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