describe_tableInspect a table or view's columns, data types, comments, primary and foreign keys before writing SQL to ensure accurate queries.
Show columns, data types, comments, primary key and foreign keys of a table or view. Use it before writing SQL.
| Name | Required | Description | Default |
|---|---|---|---|
| table | Yes | Table or view name, e.g. PURCHASE_ORDERS or ERP.ITEMS |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is fully covered. The description adds that PK/FK/comment metadata is returned, but says nothing about permissions, visibility of system schemas, or behavior on an unknown table name, so it only modestly exceeds the annotations.
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?
Two short sentences, zero filler, with the returned metadata front-loaded and the usage cue trailing. Every clause earns its place.
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 output schema, the description must convey the return shape, and it does by enumerating the returned metadata. It is complete for a single-parameter introspection tool, with only minor gaps such as error behavior for non-existent tables.
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?
Only one parameter and schema description coverage is 100%, so the schema already documents 'table' including the ERP.ITEMS qualified-name form. The description's 'table or view' phrasing mirrors rather than extends the schema, so the baseline 3 applies.
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 concrete verb ('Show') and a precisely enumerated resource: columns, data types, comments, primary key and foreign keys of a table or view. An agent can distinguish this from list_tables or run_query by the metadata it returns, though the description never names those siblings explicitly.
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?
'Use it before writing SQL' gives clear situational guidance that implicitly routes the agent away from run_query when it lacks schema knowledge. It stops short of explicit when-not conditions or naming the alternative tool, so it falls just under a 5.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.