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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety and idempotency profile is fully covered. The description adds that each entry carries a license and refresh cadence, which is useful disclosure about content, but says nothing about ordering, count, or whether any source can be stale or missing.

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?

A single front-loaded sentence that states the resource first and the returned fields second, with no filler, hedging, or repetition.

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 list with no output schema, the description covers what the tool enumerates and two of the returned fields, which is close to sufficient. A small gap remains around what constitutes a 'source' entry (e.g., vendors vs. datasets) and the approximate scale of the result.

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 there is nothing for the description to disambiguate; per the baseline rule this scores 4. The description does not need to explain any inputs and correctly does not invent any.

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 gives a specific verb (List) and resource (data sources) and narrows the scope to provenance metadata for the tree care company data, plus the fields returned (license, refresh). It is clear what the tool does, though it does not explicitly contrast itself with the sibling list_* tools beyond the distinct 'sources' resource.

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: call this when you need to know the provenance, licensing, or refresh cadence of the underlying data. There is no explicit when-to-use or when-not-to-use guidance and no named alternative, so an agent must infer the trigger.

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