Recommend indexes

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

Beyond the readOnlyHint annotation, the description adds that the tool returns a list of objects with specific fields, and provides an example. It also details the condition for recommendation (sequential scans). Some behavioral context is given.

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?

The description is concise, with one sentence and an example. Key information is front-loaded. Every sentence is meaningful and there is no redundancy.

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?

The tool has an output schema, and the description lists return fields. The only gap is the underspecified 'min_live_tuples' parameter. Otherwise, sufficient for a safe read-only tool with visible output.

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 schema has 50% coverage: only 'database' has a description; 'min_live_tuples' lacks documentation. The description mentions 'min_live_tuples' in an example but does not explain its meaning or effect. More parameter semantics are needed.

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 clearly states the tool recommends tables that may benefit from indexing, specifying the condition (large tables read mostly by sequential scan). This distinguishes it from siblings like recommend_index_drops.

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?

No explicit guidance on when to use this tool versus alternatives like recommend_index_drops. The description only implies its purpose but does not provide usage context or exclusions.

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