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

Annotations already declare the tool read-only, idempotent, and non-destructive. The description adds 'public-safe' and 'normalized source snapshots,' which hint at output characteristics but do not explain these terms or disclose other behaviors like pagination or filtering. With annotations covering safety, the extra context is moderate.

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 description is a single, front-loaded sentence that efficiently communicates the tool's core function. Every word adds value without redundancy.

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 parameterless list tool with good annotations, the description is adequate but leaves gaps: it does not clarify the meaning of 'public-safe' or 'normalized snapshots,' nor does it relate this tool to its siblings. There is no output schema, so a bit more detail on return value structure would improve completeness.

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 description does not need to explain parameter semantics. The baseline of 4 for parameterless tools applies; no additional description is required.

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 clearly states a list operation on external supply sources with a specific scope ('local public-safe') and includes output characteristics ('normalized source snapshots'). It is specific enough to differentiate from siblings like search_external_marketplaces, though it does not explicitly name alternatives.

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?

No guidance is provided on when to use this tool versus alternatives such as search_external_marketplaces or inspect_external_supply_candidate. The description simply states what it does without contextual cues for selection.

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