query_sql

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

Annotations already declare readOnlyHint=true and openWorldHint=false, but the description adds concrete operational limits beyond them: max 500 rows, 5 s execution, 2000-character truncation of text cells, and single-statement enforcement. Missing only error/timeout failure behavior and whether calling it more than once is rate-limited.

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?

One dense sentence, front-loaded with the operation and immediately followed by the hard limits. Every clause (row cap, timeout, truncation, date format) earns its place; 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 one-parameter, no-output-schema tool the description supplies the essential constraints an agent needs to avoid rejected or truncated queries. The notable gap is not pointing at describe_schema to learn tables/columns before writing SQL.

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 single 'sql' parameter has zero schema description, so the description carries the burden and does well: it constrains content to one read-only SELECT and specifies date literals as 'YYYY-MM-DD' strings. It does not document the return columns, but no fixed column set exists for arbitrary SQL.

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?

States a specific verb and resource ('Run ONE read-only SELECT on the local database') and scopes it tightly to a single statement. It is clearly the arbitrary-SQL escape hatch, though it never names or contrasts itself with the many domain getters in the sibling list.

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?

There is no explicit when-to-use guidance and no mention of alternatives such as the domain-specific getters (get_sleep, get_activity, get_trends) or describe_schema for discovering table/column names. The agent must infer that this is the ad-hoc fallback rather than call a purpose-built sibling.

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