docs: require complete automated coverage and YAML handler ownership

[adrianwebb]

Outcome

Record the user's mandatory unit + real integration + coded scene/guarantee coverage, failure/edge testing, original-budget discipline, YAML-defined agents and handler-owned task code directly in this project's AGENTS.md.

Work authority

• Work item / Issue: Implement the minimal AgentKernel, profile, and workday architecture platform#520 ; Keep agents YAML-defined and task code handler-owned, with three-layer boundary coverage agent#312
• Proposal / decision: N/A — direct user request to update every project guide.
• Assignment / checkpoint: N/A — operator documentation delivery after SDK EM terminated; no runtime assignment created.
• Actor: Codex assistant
• Human authority: Adrian, the workspace user who explicitly requested this change
• Agent / capacity provider: Codex assistant; N/A — no TreeSeed capacity-provider assignment
• Exact base ref: staging 2d7f5f9
• Exact head ref: codex/automated-coverage-guidance 5c27a24

Contributor mode (select one):

• Human-authored
• Agent-assisted under human authority
• Agent-authored under human authority

Plan

Insert the identical policy in Platform and all 17 package guides, preserve existing owner-specific guidance, verify exact read-back, then deliver checked staging PRs. This change is documentation only; runtime portability and missing coverage remain tracked separately in Agent312.

Changes and commits

5c27a24: AGENTS.md only, 19 added lines. Original guidance otherwise byte-preserved. No functional code, model/cap policy, budget, license, authority, tests or runtime selection changes.

Verification

PASS: git diff --check; exact inserted-section equality across all18 guides; original guidance unchanged outside insertion; tracked diff limited to AGENTS.md. Required GitHub Actions remain the merge gate. Functional test layers are requirements documented here, not newly completed acceptance proof. Historical SDK EM failure/freeze preserved; no SDK golden PASS claimed.

Risk and rollback

Documentation-only risk: future changes must meet the stronger coverage/ownership policy. Roll back through a reviewed revert of 5c27a24; never reset or discard unrelated user work. No migration or activation required.

Completion summary

Requested policy recorded in this project. Staging merge awaits required automated checks. No human-only staging gate introduced; no publication, tag or acceptance campaign launched.

Submission checklist

• The change is bounded to the stated work item and target repository.
• Exact base and head refs are recorded and the branch is ready for review.
• Verification and compatibility evidence are recorded above.
• No plaintext secrets, credentials, machine state, or unrelated residue are included.
• Plan, status, commits, and completion summary form a complete durable record.
• Rollback or recovery steps are documented and executable.