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

Annotations already declare this as a read-only, idempotent, non-destructive lookup. The description adds useful behavioral detail by specifying the 12-week horizon and the returned content: current level, projection, projected change, and confidence. It does not clarify confidence semantics or any plan limitations.

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 compact and front-loads the forecast horizon and output content. The fragment “Intelligence plan.” is terse and somewhat unclear, but overall the structure is efficient.

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 simple read-only forecast lookup with a fully described two-parameter schema and no output schema, the description adequately covers the forecast window and returned fields. Minor gaps remain around what “Intelligence plan” means and how confidence is expressed.

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%, so both parameters are already documented, including PackIndex examples and the currency conversion behavior. The description adds only the broad categories of PackIndex codes, not parameter syntax or additional meaning 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 states a specific resource and scope: a 12-week forward value for any PackIndex code, including current level, projection, projected change, and confidence. The 12-week forward framing distinguishes it from sibling tools like get_live_index and get_index_history.

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 forecast purpose is clear enough to imply when to use it, but the description does not explicitly name alternatives such as get_live_index or get_index_history or state when not to use this tool. The trailing “Intelligence plan” note hints at an access context without explaining it.

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