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

Annotations already declare readOnlyHint, destructiveHint=false and openWorldHint=false, so safety is covered. The description adds a genuinely useful behavioral fact the annotations do not: results are authorization-scoped ('permitted tables', 'permitted foreign-key relations'), meaning callers may see a filtered view of the catalog.

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, zero waste. The return-content inventory is front-loaded and the optional filtering constraint follows immediately, so an agent can stop reading as soon as it has what it needs.

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-required-parameter, read-only listing tool with a full output schema, the description covers scope (permitted only), parameter provenance, and returned fields. Nothing needed to invoke it correctly is missing, and return-value detail is legitimately delegated to the output schema.

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 coverage is 100% and the single parameter is self-documenting, so the baseline is 3. The description goes beyond the schema by stating that valid source values come from list_sources, which is provenance the schema itself does not supply.

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 tables) and enumerates exactly what each entry contains — display names, descriptions, columns, keys, foreign-key relations — so an agent knows the shape of the result without opening the output schema. It does not explicitly distinguish itself from describe_table, which is the closest sibling, so it falls short of a 5.

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 gives clear guidance for the single optional parameter ('restrict to one source returned by list_sources'), which ties the tool to a sibling, but it never states when to reach for this tool versus describe_table or query_table. Usage is implied rather than framed as a decision.

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