mcp-server-db2i

Describe Table

describe_table

Read-onlyIdempotent

Retrieve detailed column metadata for a DB2 for i table, including data types, lengths, nullability, defaults, and CCSID. Omit schema to use the system default.

Instructions

Get detailed column information for a specific table including data types, lengths, nullability, defaults, and CCSID. Uses the system's default schema if not provided.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`table`	Yes	Table name to describe
`schema`	No	Schema (library) name containing the table. Uses the system's default schema if not provided.

Output Schema

TableJSON Schema

Name	Required	Description
`data`	No
`count`	No
`error`	No
`filters`	No	Row filters most queries on this table need, such as leaving out deleted rows
`success`	Yes
`relations`	No
`business_description`	No

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedv3.5.0Oct 1, 2026

addedOutput schema / properties / filters

Added value: +{
+  "description": "Row filters most queries on this table need, such as leaving out deleted rows",
+  "items": {
+    "additionalProperties": false,
+    "properties": {
+      "columns": {
+        "items": {
+          "type": "string"
+        },
+        "type": "array"
+      },
+      "reason": {
+        "type": "string"
+      },
+      "sql": {
+        "type": "string"
+      }
+    },
+    "required": [
+      "sql",
+      "columns"
+    ],
+    "type": "object"
+  },
+  "type": "array"
+}

First observedv3.0.0Sep 28, 2026

TDQS

A3.7/5.0

Behavior3/5

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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive behavior, so the safety profile is covered. The description usefully adds the default-schema fallback and the fact that CCSID metadata is included, but says nothing about failure modes (e.g., unknown table/schema) or result shape, and an output schema exists anyway.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two front-loaded sentences with no filler: the purpose and returned attributes come first, then the schema-default caveat. Slightly list-heavy, but every clause carries information.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a two-parameter read tool with full schema coverage, an output schema, and annotations covering the safety profile, the definition is nearly complete. It could still note that the table must already exist or how a missing schema resolves, but no critical invocation detail is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100% and both parameters (table, schema) are already documented in the schema, including the same default-schema note. The description adds no format, qualification, or naming-convention detail beyond what the structured fields provide, so baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb ('Get') and resource ('detailed column information for a specific table') and enumerates the returned attributes (data types, lengths, nullability, defaults, CCSID), which clearly separates it from siblings like list_tables, get_object_ddl, or get_table_constraints.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies the use case (inspecting one table's column structure) but never states when to prefer this over get_object_ddl, search_columns, or list_tables, nor any conditions or exclusions. The only guidance given is the default-schema fallback behavior.

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