get_foreign_keysRetrieve foreign key relationships for a table in MySQL, PostgreSQL, SQLite, or SQL Server to identify dependencies and constraints.
Show foreign key relationships for a table on MySQL, PostgreSQL, SQLite or SQL Server
| Name | Required | Description | Default |
|---|---|---|---|
| table | Yes | Table name | |
| database | No | Optional database to read from for this call only, without changing the active connection |
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=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds the cross-database scope and indicates the output is relationship information, but does not mention return shape, ordering, or behavior for missing tables—acceptable but not rich.
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?
A single, front-loaded sentence that states the action, target, and scope without wasted words. It is efficiently structured and easy to parse.
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 tool with strong annotations and a fully documented schema, the description is largely sufficient. It could be slightly more complete by noting that a connection must be active or that a database must be selected when not using the optional parameter, but these are minor omissions.
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 100%, so the schema already documents both 'table' and 'database' parameters fully. The description adds no meaning beyond the schema, leaving the baseline of 3 appropriate.
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 states a specific verb ('Show'), a clear resource ('foreign key relationships for a table'), and distinguishes itself from siblings like describe_table or get_table_indexes by naming the exact relationship type. It also scopes supported databases, fully clarifying what the tool does.
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 clearly implies this is the right tool when an agent needs foreign key relationships for a table across four major databases. It does not explicitly name alternatives or exclusion criteria, but the sibling context and the focused wording provide sufficient usage context.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.