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

Even though annotations already mark this as read-only, the description adds substantial behavioral context: no API key is needed, it works for every served currency, it returns coverage metadata only, and it distinguishes 'no publisher produces this forecast' from 'data exists but is paywalled.' It also warns to never report listed pairs as unavailable, which is important agent-facing guidance.

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 front-loaded and well organized, but it repeats itself: the no-API-key/free access point appears twice, and the returns-no-values/subscription point appears twice. The content is useful, but a few sentences could be tightened without losing information.

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?

Given the tool's moderate complexity, a single optional parameter, an output schema, and clear annotations, the description covers all necessary context: when to call, what it returns, what it does not return, access requirements, and the paywall distinction. Nothing important is missing for correct selection and invocation.

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 schema already covers the single optional currency parameter at 100%, including the omit-for-summary vs pass-for-detail behavior. The description echoes this and adds that it works for every served currency, but does not add meaningfully new parameter-level semantics beyond the schema.

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 names a specific verb ('List') and a precise resource: which publishers produce pre-release forecasts for a currency's indicators, including forecast class, consensus status, and archive depth. It also differentiates from event_predictions by stating it is a coverage catalogue, not a values endpoint.

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?

It gives explicit invocation rules: call it whenever the user asks whether a consensus or forecast exists, call it BEFORE event_predictions, and call it when event_predictions returns nothing or subscription_required. It also clarifies that forecast values are not returned and require a subscription, effectively stating when not to rely on this tool.

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