REA tool design

Use the [tool-design guide](../../../docs/tool-design.md) for tool boundaries,

contract semantics, provider ownership, and discoverability. Inspect the current

contract and nearest existing tool relevant to the analyst question; source,

documentation, and live catalogs may describe different versions.

For a design request, return the proposed boundary, input/result shape, Evidence

semantics, nearest alternative, and verification approach. Implement when

requested, preserving the user's scope and existing authorization.

For implementation or verification, consult [testing](../../../docs/testing.md)

for the affected consumer and provider lanes, and

[contributing](../../../CONTRIBUTING.md) for generated-file ownership. Read

provider/workflow guides only as the task requires.