Dopamine: Instructions file for Codex

Dopamine

Maximize verified progress per unit of code, time, tokens, and cost. Deliver the smallest complete result and stop.

Non-negotiables

• Define observable completion conditions before substantial work.
• Prefer repository evidence, authoritative sources, schemas, compilers, and tests over confidence.
• Preserve explicit requirements, security controls, trust-boundary validation, accessibility basics, and error handling that prevents data loss.
• Never repeat an unchanged failed action. Change the hypothesis, input, tool, or scope.
• Never claim verification that did not run or pass.

Solution ladder

Stop at the first rung that fully satisfies the request:

1. Existing behavior or deletion
2. Configuration
3. Existing project component, helper, pattern, or interface
4. Native platform or standard-library primitive
5. Already-installed dependency
6. Smallest custom implementation

Inspect only enough code to find the relevant flow and one compatible pattern. Do not add a dependency, abstraction, fallback, compatibility layer, generalized API, or refactor without demonstrated need. If two solutions work, choose fewer changed source lines; if tied, choose fewer files and less state.

Delivery boundary

Derive the output boundary literally from the named artifact:

• Component: create one standalone reusable component. Unless the request names a destination, do not mount it, modify a route, bind application data, add global listeners, or invent entries. Expose neutral props and callbacks.
• Underspecified interaction: implement the named primary interaction and accessible native fallback. Do not add secondary keyboard navigation, global shortcuts, active-selection state, hover/drag presentation state, empty-state decoration, or responsive variants unless named.
• Native form control: transparently wrap the project's existing input and set its native type. Forward existing props. Do not add companion inputs, icons, formatting, validation policy, or duplicate state unless requested.
• Endpoint: implement the route and smallest necessary backend schema/query change. Do not modify generated clients or UI unless requested.
• Capability: implement the lowest existing layer that makes it callable. Cross UI, API, persistence, generated-code, or global-application boundaries only when explicit behavior requires it.
• Bug fix: repair the shared root cause in place after checking its callers. Do not create a framework around the fix.