list_security_roles

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

With no annotations, the description carries the burden and does disclose meaningful behavior: it returns per-table filter expressions and flags tables visible with no row filter, and it warns that RLS is not surfaced unless queried. It doesn't state permission requirements or confirm read-only semantics explicitly, but 'List' plus the described output makes the read-only profile clear enough.

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 resource and the unfiltered_tables flag are front-loaded, and the closing sentence justifies the tool's existence rather than padding. Slightly verbose in the second half but every sentence adds information an agent can act on.

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?

An output schema exists, so return-value explanation is not needed, and the description covers the salient output concept (unfiltered tables). The undocumented required 'instance' parameter leaves a real hole for an agent deciding how to invoke it, so it is only minimally complete.

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 required parameter 'instance' has 0% schema description coverage and the description says nothing about what an instance refers to, what format it takes, or which instance to pass. For a one-parameter tool this is the only real gap, but it is a complete one.

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 ('List row-level security (RLS) roles and each one's per-table filter expression') and adds a distinguishing output trait (unfiltered_tables flag). No sibling tool covers RLS, so the agent can identify it unambiguously from the name plus description.

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?

Explicitly frames when this tool matters: 'RLS is invisible unless specifically checked, so this is exactly the kind of thing a "who can see what" or security-focused review needs.' That is a clear trigger condition. It stops short of naming an alternative or an explicit when-not-to-use case, which keeps it below a 5.

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