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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds genuine behavioral context - that only a public-safe subset is returned and internal partner/marketing guidance is filtered out - which is useful, but it omits return format, currency/scope limits, or any rate considerations.

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 sentences, front-loaded with the primary return value before the filtering caveat and the disclaimer. Efficient overall, though the trailing advice disclaimer is marginal to tool selection.

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?

Because an output schema exists, the description needn't explain return values, and with no parameters and clear annotations the burden is light. It adequately covers what the tool is and how the returned set is scoped; only alternative-routing guidance is missing.

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 no parameters. With zero inputs and 100% schema coverage, there is nothing for the description to clarify, so the baseline of 4 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?

States a specific verb and resource ('Returns Hedgr's shared FX-guidance canon') and clarifies it is read-only methodology. The FX-specific framing separates it from generic siblings like get_policy, though it never explicitly names a sibling it is distinct from.

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 explains what the tool returns but gives no when-to-use or when-not-to-use guidance, and never references alternatives such as get_policy or get_rate_assumptions. An agent must infer the invocation context purely from content description.

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