db_schemaInspect a SQLite database's tables and columns to orient yourself before writing queries. Returns schema details only, without creating missing files.
Lists tables and their columns in a SQLite database — orientation before writing queries. Does not create the file if it's missing.
| Name | Required | Description | Default |
|---|---|---|---|
| db_path | Yes |
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
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 and idempotentHint, so the safety profile is handled. The description adds a valuable behavioral caveat — 'Does not create the file if it's missing' — which goes beyond the annotations and helps predict tool behavior.
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 sentences, no filler, with the core behavior first and the important side-effect caveat second. 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?
For a simple read-only one-parameter tool with annotations and an output schema, this is nearly complete. The only minor gap is that the behavior when the file is missing is only partially disclosed — it won't create the file, but whether it errors or returns empty is left unspecified.
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 carries the burden for the single db_path parameter. The wording 'in a SQLite database' and 'file' imply db_path is a path to a SQLite file, but the description never explicitly documents the parameter's type or format beyond the schema's string type.
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 uses a specific verb ('Lists') and resource ('tables and their columns in a SQLite database'), and immediately clarifies its orientation role before query writing. This clearly distinguishes it from db_query/db_execute and other file operations.
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?
'Orientation before writing queries' gives a clear context for when the tool is appropriate, but it does not explicitly name alternatives or state when not to use it. The positioning against query/execute siblings is implied rather than explicit.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.