list_tables

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

No annotations are provided, so the description must carry the behavioral burden. 'List' and 'Call this first' imply a safe, read-only discovery operation, and the description clarifies that both tables and views are included. However, it does not disclose details such as whether system schemas are included or how results are ordered, though the output schema covers return value structure.

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 with no filler. The first sentence states the action and resource, and the second provides a clear usage directive. Every word 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 zero-parameter discovery tool with an output schema and clear sibling context, the description is fully adequate. It tells the agent what the tool returns, when to call it, and how it fits into the workflow.

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?

The tool takes zero parameters, so the description does not need to explain parameter meaning. With no parameters to document, the baseline of 4 applies because there is nothing the schema requires the description to supplement.

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-resource pair, 'List all tables and views in the database,' which clearly identifies the operation's scope. The phrase 'Call this first' also positions it as a discovery/entry-point tool, distinguishing it from siblings like describe_table, get_schema, and run_query.

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?

'Call this first to see what data exists' gives explicit guidance on when to invoke the tool. It does not explicitly state when not to use it or mention alternatives, but for a simple discovery tool the primary usage context is clear.

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