Recommend indexes

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

The description explicitly states 'Read-only — recommends, never alters the schema' and 'Local files only,' which adds valuable context beyond the annotations (readOnlyHint, destructiveHint). This clarifies the read-only nature and file access constraint.

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 two sentences, front-loaded with the main purpose ('Analyze...'), and each sentence adds value without redundancy. It is concise 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?

Given the output schema exists (implied), the description adequately explains the inputs and behavior. It lists specific diagnostics (foreign keys, redundant indexes, table scans) but does not mention potential limitations or error cases, which is acceptable for a read-only tool.

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 input schema covers both parameters with descriptions (source path, optional queries). The description adds no additional meaning beyond the schema, such as formats or constraints. With 100% schema coverage, baseline 3 is 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 starts with 'Analyze a local SQLite database for performance problems and recommend fixes' which clearly states the action and resource. It lists specific types of problems (foreign keys, redundant indexes, full table scans) and distinguishes from sibling tools like litescope_query (executes queries) and litescope_schema (shows schema).

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 explicitly states the tool's purpose and output (recommendations with runnable SQL), making it clear when to use it. However, it does not explicitly state when not to use it or name alternative tools, though the sibling context helps.

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