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

Annotations already declare readOnlyHint=true and openWorldHint=false, and the description goes further by enumerating exactly what is read (catalog metadata: table/column names, RLS flags, policies, grants, triggers, SECURITY DEFINER functions, bucket settings) and explicitly promising that table rows are never touched. It also discloses the return shape as a single JSON value. It does not mention any auth requirements or rate limits, so it falls short of the top mark.

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 sentences, with the core purpose front-loaded before the scope details. The parenthetical enumeration is long but each item is informative and replaces a separate paragraph, so there is no waste.

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, read-only tool with no output schema, the description gives enough context to call it: what it returns, what it touches, and what it never touches. It could be slightly more complete by stating whether it executes anything or how the JSON is structured, but it is sufficient.

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 baseline is 4. The description does not attempt to describe parameters and correctly implies there are none, saying only that the SQL and how to run it are returned.

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 states a specific verb and resource: it returns read-only SQL for the live Supabase check, plus instructions on how to run it. That clearly distinguishes it from a tool that actually performs the check, though it never names the sibling check_supabase_snapshot, so the differentiation is only implied.

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?

Usage is implied rather than stated: an agent can infer this is for getting the query text and run instructions rather than executing the check. There is no explicit when-to-use versus when-not guidance, and no mention of the alternative tool for actually performing the check.

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