list_sources

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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so the safety profile is covered. The description adds genuinely non-derivable context: it consumes the existing API key under plan access, rate limits and row allowances, and that returned source text is untrusted data — an important prompt-injection caveat for an open-world read.

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?

Three short sentences, front-loaded, with no padding; the auth/quota and untrusted-data notes each earn their place. The opening sentence is near-redundant with the name, so it is concise but not maximally informative per word.

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-optional-param read tool with strong annotations, the operational context (auth, quota, trust) is adequately covered. What remains missing is the semantic core: what a "source" record actually contains and roughly what is returned, which the description must supply since there is no 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 description coverage is 100% and the single optional enum parameter is fully documented in-schema, including the omit-for-default and exclusivity rules. The description adds no additional meaning about the category values or their effect on results, so the baseline of 3 applies.

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?

"List sources" is essentially the tool name restated with a verb; it never says what a "source" is (a data-source catalog entry? a document? a feed?) and gives no differentiation from the many sibling search_* tools. The only substantive scoping hint ("original property feed catalog" vs. a category) lives in the schema, not the 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?

There is no when-to-use guidance and no mention of alternatives — an agent cannot tell from the description whether to call list_sources first to discover feeds or to go straight to search_properties / trustee_sales_search. The only usage constraint ("supply one category and no other parameters") appears in the parameter schema rather than the description.

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