execute_readonly_sql

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

With no annotations, the description carries the full burden and does so thoroughly: it discloses that the database is opened read-only, that refused mutations leave the file unchanged, states that stacked statements are rejected, and explains pagination defaults and the response format. This goes well beyond what the schema or annotations alone would reveal.

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 dense but structured: it front-loads the primary action, then lists allowed/rejected statements, pagination behavior, and return contract. Every sentence contributes a distinct constraint with no filler.

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 3-parameter tool with an output schema and no annotations, the description covers the SQL grammar constraints, safety guarantees, pagination limits, error behaviors, and guidance for choosing a sibling tool. Nothing essential to correctly invoking it is missing.

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 compensates by defining the 'sql' parameter in terms of allowed statement types and by providing concrete limits for 'limit' (default 100, max 1000) and 'offset' (default 0). All three parameters gain usable meaning.

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 opens with an exact verb and resource: 'Run a single read-only SQL statement against shop.db.' It further specifies the allowed statement forms (SELECT, WITH/CTE, EXPLAIN) and explicitly distinguishes itself from the shop_analytics sibling for rankings/revenue, making the tool's purpose unambiguous.

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 says to 'Prefer shop_analytics for rankings and yearly revenue,' naming an alternative and the scenario where it should be used. It also sets clear boundaries for this tool by enumerating what is allowed (read-only SELECT, WITH, EXPLAIN) and rejecting writes/DDL and stacked statements.

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