Implement with Sol

Deliver the authorized milestone as a coherent, correct, and maintainable whole. Astra leads and delegates implementation to Sol where a bounded contract and adequate evidence justify the handoff. Direct implementation remains useful when the work needs shared, changing context or the handoff adds little value.

Selection and authority

Invoke $implement-with-sol in an Astra session. This skill does not change the lead's model or reasoning effort. The selection applies to the current milestone unless the user specifies a different scope within the implement stage.

Run heddle orient and follow its next actions. Read heddle/resources/implement.briefing.md and the governing records. The user's request and governing Heddle and repository authority take precedence over this skill and its assignments. This skill changes execution style, not scope, stage authority, test authority, or review policy.

If Heddle-owned guidance is absent from the host checkout, use heddle doctor --json to locate the installation. Read an editable checkout's resources where available; otherwise use native help and routed briefings, identifying any remaining guidance gap.

Assigning work

Choose between direct work and delegation by uncertainty, consequence, coupling, and verifiability. Retain consequential shared reasoning and integration with the lead. Give Sol a cohesive outcome with settled inputs, clear ownership, and observable completion criteria.

Build the assignment with heddle/resources/work-package-brief.scaffold.md. Use the existing specification, milestone scope, scaffolded tests, consumer contracts, and applicable verification authority. Supply the context and operative instructions the worker needs without prescribing reversible implementation choices. A defect in those inputs is a discovery to resolve through the governing workflow, not permission to weaken the contract.

Use sol-implementer, defined in .codex/agents/sol-implementer.toml. Its reasoning effort is pinned to xhigh. Check the active harness's model, context, and permission controls. Surface an unavailable agent, model, or effort level rather than silently substituting one or claiming the requested configuration ran. The custom agent's instructions are behavioral constraints; workers inherit the active harness permissions.

Execution and handoff

The lead may supervise multiple Sol workers in parallel when their work packages are independent, shared contracts are settled, write ownership does not overlap, and the integration order is clear. One owner may write a given path at a time. The lead may implement a separate package concurrently under the same rule. If an overlap, dependency, or shared-contract change emerges, pause the affected package and re-brief it from current source before writing continues.

The lead tracks package ownership, dependencies, and source identities while retaining commits, Heddle mutations, governing-document changes, integration, and formal review within its existing authority. Integrate in dependency order and rerun affected evidence on the integrated source; a worker's passing result can become stale after another package lands.

Inspect the returned changes and evidence against the governing requirements and actual consumers. Resolve consequential gaps before dependent work. Reuse worker context when it remains useful; change the assignment or implement directly when that better addresses the source of uncertainty. Follow native verification, review, remediation, and completion requirements. Do not add an extra verifier without a distinct evidence need; supplementary assessment does not replace formal review.

When the user selects standard implementation, finish or stop the active worker's handoff before the lead resumes writing. Preserve its changes, inspect the resulting source, and record remaining work in the existing handoff. Changing execution style neither discards evidence nor establishes that it still applies.