# Skill OS 2.0 Review

Review date: 2026-06-13
Scope: Yao Meta Skill against the user-provided Skill OS 2.0 upgrade plan.

## Verdict

Yao Meta Skill is no longer only a Meta Skill factory. The current working tree now has the first verifiable Skill OS foundation:

- Skill IR v0 for platform-neutral contract capture.
- Output Eval Lab v0 for with-skill vs baseline assertion grading plus local command-runner execution evidence, blind A/B review pack, separate answer key evidence, and reviewer adjudication reporting.
- Runtime Conformance v0 for target-consumption checks.
- Trust/Security v0 for secret, dependency, script, bounded network host policy, execution-level CLI help smoke checks, trust metadata, and stable source-contract integrity checks.
- Skill Atlas v0 for portfolio catalog, route overlap, stale ownership, dependency signals, aggregate drift signals, and no-route opportunities.
- Bilingual Skill Overview v2 that includes these evidence surfaces.
- Skill OS 2.0 Audit v0 for requirement-by-requirement evidence mapping, with explicit separation between local evidence, human-required review, and external-required provider/client integrations.
- World-Class Evidence Plan v0 that turns the remaining provider holdout, human adjudication, native permission enforcement, and native client telemetry gaps into executable runbooks with success checks and privacy contracts.
- World-Class Evidence Ledger v0 that records current acceptance state, provenance requirements, privacy contracts, and anti-overclaim guards for those remaining gaps.
- Benchmark Reproducibility v0 that turns public benchmark methodology, required artifacts, failure disclosure, and reproduction commands into machine-checkable release evidence.
- Review Studio 2.0 v0 for one-page blocker, warning, evidence-path, review-action, and release-gate review.
- Review Studio Source Refs v0 so every non-pass review action can expose structured relative source/report links with best-effort line numbers.
- Target Compiler v0 so Skill IR compiles into OpenAI, Claude, generic, Agent Skills compatible, and VS Code / Copilot target contracts before packaging, including target-specific permission contracts and native behavior contracts.
- IR-first packaging v0 so adapters carry the platform-neutral semantic contract, compiler contract, parity checks, IR provenance, and VS Code / Copilot install-scope notes where applicable.
- Registry & Distribution v0 for package metadata, checksum, owner, license, compatibility matrix, and audit reporting.
- Package Verification v0 for generated manifest, target adapters, zip archive safety, archive checksum, and registry parity.
- Install Simulation v0 for local extraction, entrypoint loading, interface loading, report presence, adapter readability, and installer-level permission approval/enforcement checks.
- Upgrade Check v0 for registry package diffs, semver bump recommendations, breaking-change notes, and release evidence.
- Adoption Drift v0 for local-first metadata-only telemetry, privacy-field blocking, usage-signal aggregation, iteration candidate generation, and Skill Atlas drift-signal input.
- CLI Telemetry Capture v0 for opt-in `yao.py` command-run metadata that records command name, source, outcome, failure class, and timestamp without command arguments or raw user/model content.
- External Telemetry Import v0 for whole-file validated metadata-only JSONL ingestion from non-CLI clients, with dry-run support and all-or-nothing rejection on raw content fields or schema violations.
- Telemetry Emit Hook v0 for Browser/Chrome/IDE/wrapper integrations to append one validated metadata-only external event into a local spool before import, with dry-run validation and raw-content blocking.
- Telemetry Hook Recipes v0 for Browser, Chrome, VS Code, CLI wrapper, and provider-adapter recipe generation with dry-run commands, metadata-only privacy checks, and explicit non-claiming of native host integration.
- Telemetry Native Host v0 for Browser/Chrome Native Messaging length-prefixed stdio, metadata-only event validation, local launcher generation, and Chrome host manifest generation.
- Review Waivers v0 for human warning acceptance with reviewer, reason, scope, expiry, and blocker-safe policy.
- Governed Permission Gates v0 for reviewer-approved network, file-write, and subprocess capabilities with scope, reason, expiry, evidence, and target-enforcement mapping.
- Runtime Permission Probes v0 for packaged target adapter checks, explicit native-enforcement flags, metadata fallback evidence, and residual permission risks.
- Local Install Sync Preflight v0 so source-to-local and source-to-active install syncs rebuild the package first, run install simulation, enforce installer permission coverage, and refuse to copy files before any destructive sync when the package is not install-ready.
- Atlas Scope Policy v0 so examples, evolution snapshots, embedded generated skills, and validator fixtures remain visible in the full portfolio report without polluting release-actionable gates.
- Review Annotations v0 for reviewer comments tied to Review Studio gates, source/report paths, and optional line numbers; open blocker annotations now block the Review Studio decision.
- Review Studio now avoids over-claiming release readiness when blind A/B adjudication and world-class evidence are still pending: the root Meta Skill is in `review` with score `90`, no blockers, three warnings, and explicit actions for Output Lab reviewer adjudication, waiver handling, and world-class evidence completion.
- Review Studio Output Lab actions now link directly to `reports/output_review_decisions.json`, so pending blind A/B reviewer decisions have a concrete template instead of only a general adjudication warning.
- Output Review Adjudication now preserves blind-review integrity by hiding expected winners for pending or invalid reviewer decisions; answer keys are revealed only after a valid A/B decision exists for that case.
- Provider Output Eval Runner v0 so `python3 scripts/yao.py output-exec --provider-runner openai` can collect real provider-backed model evidence through a reviewed OpenAI Responses API compatible runner instead of ad hoc shell glue.

This is still not the final world-class state. Target-native behavior contracts are now explicit, VS Code / Copilot package metadata is auditable, local output-eval command execution is wired, blind-review answers remain hidden until valid decisions exist, a provider-backed output runner exists, installer-level permission coverage is now locally enforced during install simulation and local install sync, opt-in `yao.py` CLI telemetry can capture metadata-only real run signals, external clients can now emit one validated metadata-only event into a local spool, hook recipes now make Browser/Chrome/VS Code/wrapper/provider-adapter integration commands auditable, a Browser/Chrome Native Messaging host can receive length-prefixed metadata events and generate a local launcher plus manifest, validated external JSONL imports can bring those non-CLI client signals into the same drift loop, and Skill Atlas now consumes aggregate drift reports. Review Studio keeps pending human adjudication and pending world-class evidence visible as warnings instead of treating them as a clean pass. Deeper provider-native execution transforms, installed platform-native client telemetry implementations, provider-native installer integration, real provider holdout runs, real human adjudication decisions, accepted external evidence, and native runtime permission enforcement remain open.

## Coverage Matrix

| 2.0 Area | Current Evidence | Status |
| --- | --- | --- |
| Skill IR | `skill-ir/schema.json`, `skill-ir/examples/yao-meta-skill.json`, `scripts/export_skill_ir.py` | v0 landed |
| Target Compiler | `scripts/compile_skill.py`, `reports/compiled_targets.md`, `tests/verify_compile_skill.py` | v0 landed |
| Output Eval Lab | `evals/output/cases.jsonl`, `scripts/run_output_eval.py`, `scripts/run_output_execution.py`, `scripts/local_output_eval_runner.py`, `scripts/provider_output_eval_runner.py`, `scripts/adjudicate_output_review.py`, `reports/output_quality_scorecard.md`, `reports/output_execution_runs.md`, `reports/output_blind_review_pack.md`, `reports/output_blind_answer_key.json`, `reports/output_review_decisions.json`, `reports/output_review_adjudication.md` | v0 landed |
| Benchmark methodology | `reports/benchmark_methodology.md` | v0 landed |
| Benchmark Reproducibility | `scripts/render_benchmark_reproducibility.py`, `reports/benchmark_reproducibility.md`, `tests/verify_benchmark_reproducibility.py` | v0 landed |
| Skill OS 2.0 Audit | `scripts/render_skill_os2_audit.py`, `reports/skill_os2_audit.md`, `tests/verify_skill_os2_audit.py` | v0 landed |
| World-Class Evidence Plan | `scripts/render_world_class_evidence_plan.py`, `reports/world_class_evidence_plan.md`, `tests/verify_world_class_evidence_plan.py` | v0 landed |
| World-Class Evidence Ledger | `scripts/render_world_class_evidence_ledger.py`, `reports/world_class_evidence_ledger.md`, `tests/verify_world_class_evidence_ledger.py` | v0 landed |
| Runtime Conformance | `scripts/run_conformance_suite.py`, `reports/conformance_matrix.md` | v0 landed |
| Trust & Security | `scripts/trust_check.py`, `reports/security_trust_report.md`, `security/*.md` | v0 landed |
| Review Studio 2.0 | `scripts/render_review_studio.py`, `reports/review-studio.html`, `reports/review-studio.json` with per-warning `review_actions` | v0 landed |
| Review Studio Source Refs | `scripts/render_review_studio.py`, `tests/verify_review_studio.py`, `references/review-studio-method.md` | v0 landed |
| Review Annotations | `scripts/render_review_annotations.py`, `reports/review_annotations.md`, `tests/verify_review_annotations.py`, Review Studio annotation panel and blocker decision hook | v0 landed |
| Skill Atlas | `scripts/build_skill_atlas.py`, `skill_atlas/catalog.json`, `skill_atlas/route_overlap_matrix.csv`, `skill_atlas/drift_signals.json`, `reports/skill_atlas.html` | v0 landed |
| Registry & Distribution | `registry/*.schema.json`, `scripts/registry_audit.py`, `reports/registry_audit.md`, `registry/packages/yao-meta-skill.json` | v0 landed |
| Package Verification | `scripts/verify_package.py`, `reports/package_verification.md`, `tests/verify_package_verification.py` | v0 landed |
| Install Simulation | `scripts/simulate_install.py`, `reports/install_simulation.md`, `tests/verify_install_simulation.py` with installer permission coverage checks | v0 landed |
| Local Install Sync Preflight | `scripts/sync_local_install.py`, `tests/verify_local_install_sync.py`, `Makefile` package-check prerequisites | v0 landed |
| Upgrade Check | `scripts/upgrade_check.py`, `reports/upgrade_check.md`, `tests/verify_upgrade_check.py` | v0 landed |
| Telemetry & Drift | `scripts/render_adoption_drift_report.py`, `scripts/yao_cli_telemetry.py`, `scripts/emit_telemetry_event.py`, `scripts/render_telemetry_hook_recipes.py`, `scripts/telemetry_native_host.py`, `scripts/import_telemetry_events.py`, `reports/adoption_drift_report.md`, `reports/telemetry_hook_recipes.md`, `tests/verify_adoption_drift.py`, `tests/verify_telemetry_emit.py`, `tests/verify_telemetry_hooks.py`, `tests/verify_telemetry_native_host.py`, `tests/verify_telemetry_import.py`, `tests/verify_yao_cli.py`, `references/telemetry-drift-method.md` | v0 landed |
| Review Waivers | `scripts/render_review_waivers.py`, `reports/review_waivers.md`, `tests/verify_review_waivers.py`, `references/review-waiver-method.md` | v0 landed |
| Governed Permission Gates | `security/permission_policy.json`, `scripts/trust_check.py`, `scripts/render_review_studio.py`, `tests/verify_trust_check.py`, `tests/verify_review_studio.py` | v0 landed |
| Runtime Permission Probes | `scripts/probe_runtime_permissions.py`, `reports/runtime_permission_probes.md`, `tests/verify_runtime_permission_probes.py`, `tests/verify_review_studio.py` | v0 landed |
| Atlas Scope Policy | `skill_atlas/policy.json`, `scripts/build_skill_atlas.py`, `tests/verify_skill_atlas.py` | v0 landed |
| Compiler from IR | Packager consumes compiled target contracts for compiler provenance, generated files, adapter modes, permissions, preserved semantics, warnings, and unsupported features | v0 landed |
| Target Native Contracts | `scripts/compile_skill.py`, `scripts/cross_packager.py`, `reports/compiled_targets.md`, adapter snapshots, and generated target outputs carry native surface, activation policy, resource/script strategy, permission enforcement, install scope, review artifacts, fallback behavior, and unsupported native features | v0 landed |

## Top Findings

### 1. Target-native behavior contracts are landed, but provider execution is still shallow

`scripts/compile_skill.py` now reads Skill IR and emits target-specific contracts for OpenAI, Claude, generic, Agent Skills compatible, and VS Code / Copilot outputs. The packager embeds `compiler`, `compiled_contract`, `permission_contract`, `target_permission_contract`, `target_native_contract`, `target_transform`, warnings, and unsupported-feature notes in each adapter. The native contract makes the target surface, activation policy, resource strategy, script strategy, permission enforcement mode, install scope, review artifacts, fallback behavior, and unsupported native features reviewable instead of implicit.

Next move: deepen provider-native execution transforms so OpenAI, Claude, VS Code/Copilot, and generic packages can express and verify behavior through real client or installer capabilities, not only auditable contracts and fallback notes.

### 2. Output eval now has command-runner evidence, but provider model execution is still open

The v0 cases now cover five scenarios, including near-neighbor and file-backed governed package cases. Each run emits assertion grading, execution provenance, a blind A/B review pack that hides baseline vs with-skill labels, a separate answer key, and an adjudication report from reviewer choices. The current root execution report now runs all `10` variants through `scripts/local_output_eval_runner.py`, so timing and command-runner behavior are observed instead of relying only on static recorded fixtures. The new `scripts/provider_output_eval_runner.py` gives teams a reviewed OpenAI Responses API compatible path for real model execution. The root evidence still intentionally reports `0` provider-backed model-executed runs and `10` estimated token counts, because no real provider holdout run has been recorded in this release evidence. The current root adjudication report intentionally records `0 / 5` human judgments pending instead of pretending human review happened. The next gap is running provider-backed holdout cases with real provider timing/tokens and recording real reviewer decision records.

Next move: run provider-backed holdout cases with real credentials and one real multi-file fixture, then record actual reviewer decisions.

### 3. Review Studio is unified and now has reviewer actions plus annotations

The Review Studio page aggregates intent, trigger, output, context, runtime, trust, permission approvals, runtime permission probes, atlas, operations-loop, reviewer waiver, reviewer annotations, registry, world-class evidence, and release gates. It exposes current warnings directly and emits `review_actions` for each non-pass gate with a source-fix location, structured `source_refs`, reason, evidence path, and verification command. It now also loads `reports/review_annotations.json`, renders reviewer comments tied to gates and source/report paths, and blocks the page decision when any open blocker annotation exists. The current root report is intentionally not a clean pass: decision `review`, score `90`, `14` gates, `0` blockers, `3` warnings, `3` actions, and `0` open annotation blockers. The warnings are useful evidence: the automated Output Eval Lab is strong, but the blind A/B adjudication still has `5` pending reviewer decisions and the world-class ledger still has `4` pending external or human evidence entries, so the package should not claim fully reviewed or world-class status.

Next move: add richer source-line anchors inside generated reports, record real reviewer annotations during the next human review pass, and close the provider, native-permission, real-client telemetry, and human review evidence entries in the world-class ledger.

### 4. Multi-skill operation now links Atlas with drift, but needs platform-native capture

The new Skill Atlas can scan a workspace and report catalog, route overlap, dependency graph, stale skill, missing owner/review metadata, aggregate drift signals, and no-route opportunities. It now also supports `skill_atlas/policy.json` so release gates distinguish actionable library skills from examples and fixtures while keeping full visibility. Adoption Drift v0 can record metadata-only local events, block raw prompt/output fields, summarize missed-trigger, bad-output, script-error, and review-overdue signals, feed next iteration candidates into Review Studio, and publish aggregate drift input for Atlas. `yao.py` now adds opt-in automatic CLI run capture through `YAO_CLI_TELEMETRY=1` or `--record-cli-telemetry`, recording only `source=yao_cli`, normalized subcommand name, outcome, failure class, and timestamp. `telemetry-emit` gives Browser/Chrome/IDE/wrapper integrations a stable local hook for appending one normalized external event into `.yao/telemetry_spool/external_events.jsonl`, with dry-run validation and no raw content fields. `telemetry-hooks` renders Browser, Chrome, VS Code, CLI wrapper, and provider-adapter recipes with dry-run commands, import commands, trigger points, and explicit `native_auto_capture=false` caveats. `telemetry_native_host.py` now provides a tested Browser/Chrome Native Messaging host: it reads length-prefixed stdio JSON, rejects raw content fields, writes metadata-only events, and generates an operator-installable launcher plus Chrome host manifest. `telemetry-import` accepts already-sanitized external client JSONL or the emitted spool, validates the whole file before appending, supports dry-run, defaults `source=external`, and rejects any raw content or unknown metadata fields without mutating the local event stream. It still needs an installed real extension or provider client that sends production events to the native host.

Next move: install a real Browser/Chrome extension or provider client against the native host and record production metadata events, then let Atlas rank stale, drifting, or conflicting skills by real usage impact.

### 5. Trust report is structural, not full security review

Trust v0 blocks obvious secrets and remote inline execution, and now makes checksum scope explicit: `package_sha256` is a stable source-contract digest that excludes generated reports, packages, and raw local telemetry; archive integrity is carried by Package Verification and Registry as `archive_sha256`. Registry v0 carries both checksums into distributable metadata. Package Verification v0 now checks generated manifests, target adapters, archive path safety, required source entries, and registry parity. Install Simulation v0 now extracts the generated archive into a temporary local skill root, verifies entrypoint, manifest, interface, reports, and adapters, then checks every packaged target/capability pair against the installed `security/permission_policy.json` approval and `target_enforcement` mapping. Local Install Sync Preflight now runs the same install simulation before syncing source into the disabled or active local install path, so a broken package or permission enforcement gap fails before stale files are removed or new files are copied. Upgrade Check v0 now compares package baselines, recommends semver bumps, and blocks breaking changes without an adequate declared version. Trust Report now distinguishes CLI scripts from declared internal modules, so help-surface warnings focus on executable entrypoints. Network-capable scripts are now covered by `security/network_policy.json`, with `allowed_hosts` checked against HTTPS URL literals. Trust Report also executes `python3 scripts/name.py --help` for CLI scripts with `argparse`, recording pass/fail smoke evidence without executing scripts that lack a help surface. Target adapters now carry `permission_contract` and `target_permission_contract` fields, including network, file-write, subprocess, and interactive capability counts. Governed permission gates now require reviewer-approved scope, reason, expiry, evidence, and target-enforcement mapping in `security/permission_policy.json`. Runtime Permission Probes now verify that packaged adapters expose the target permission contract and explicitly report native-enforcement limits. The remaining trust gap is native runtime permission enforcement in real clients/installers.

Next move: add real client or installer permission enforcement integration.

## Current Gate Evidence

| Gate | Current Result |
| --- | --- |
| Output Eval | `5` cases, with-skill pass rate `100`, baseline pass rate `0`, with file-backed, near-neighbor, boundary coverage, `10` local command-runner execution runs, `0` recorded fixture runs, `0` provider model-executed runs in root release evidence, `10` estimated token counts, provider runner v0 available, `5` blind A/B review pairs, a generated `reports/output_review_decisions.json` template, `0 / 5` reviewer decisions pending, `0` answer keys revealed, and `5` pending answers hidden |
| Runtime Conformance | `5 / 5` targets passing |
| Target Compiler | `5 / 5` compiled target contracts generated for OpenAI, Claude, generic, Agent Skills compatible, and VS Code / Copilot outputs, including target permission contracts and target-native behavior contracts |
| Trust | `0` secret findings, `1` pinned dependency file, `10` declared internal modules, `3 / 3` network-capable scripts covered by bounded host policy, `68 / 68` CLI help smoke checks passing across `78` scripts, source-contract hash scope explicit |
| Permission Governance | `3 / 3` required high-permission capabilities approved, `0` missing, `0` invalid, `0` expired |
| Runtime Permission Probes | `4 / 4` target adapters probed, `0` native-enforcement adapters, `4` explicit metadata fallbacks, `4` residual risks retained for reviewer visibility |
| Skill Atlas | `12` scanned skills, `1` actionable root skill, `1` telemetry report, `0` actionable route collisions, `0` actionable owner gaps, `0` actionable stale skills, `0` actionable drift signals, `24` scoped non-actionable issue signals retained for visibility |
| Registry Audit | package metadata generated with version, owner, license, source checksum, archive checksum, Skill IR provenance, and compatibility matrix |
| Package Verification | `4 / 4` target adapters present, archive verified, `521` zip entries, `0` failures, `0` warnings |
| Install Simulation | archive with `521` entries extracted into a local verification root, entrypoint/manifest/interface loaded, reports present, `4` adapters readable, `12` installer permission checks enforced, `0` permission failures, `0` failures, `0` warnings |
| Local Install Sync Preflight | `make sync-local-install` and `make sync-active-install` rebuild the package first, then sync only after install simulation passes with `12` enforced installer permission checks and `0` permission failures |
| Upgrade Check | current package declares `minor` over the 1.0.0 baseline, recommended bump is `minor`, and release notes include added targets plus checksum changes |
| Adoption Drift | `1` metadata-only review event, `0` adoption samples, adoption `0`, risk band `low`; optional `yao.py` CLI capture, external client `telemetry-emit`, `5` `telemetry-hooks` recipes, Browser/Chrome native messaging host, and validated external JSONL import are available but off by default for reproducible release evidence; raw `reports/telemetry_events.jsonl` is gitignored and blocked from zip packages |
| Review Waivers | ledger generated; current release has `1` warning gate that still needs reviewer decision or a time-bounded waiver; blockers remain non-waivable in v0, and world-class evidence gaps must be closed with accepted evidence rather than waived as completed |
| Review Annotations | ledger generated; current release has `0` reviewer annotations and `0` open annotation blockers |
| Review Studio | decision `review`, world-class score `90`, `14` gates, `0` blockers, `3` warnings, `3` review actions, `0` open annotation blockers |
| Skill OS 2.0 Audit | `15` audited areas, with local foundation evidence separated from human-required and external-required gaps |
| World-Class Evidence Plan | `4` remaining evidence tasks: `1` human-required and `3` external-required, all with runbooks, success checks, and privacy contracts |
| World-Class Evidence Ledger | `4` evidence entries remain pending: `1` human-required and `3` external-required; anti-overclaim guards block planned work, metadata fallbacks, pending review, and local command runners from counting as completion |
| Benchmark Reproducibility | local reproducibility ready with `17` required artifacts, `0` missing artifacts, `16` reproduction commands, and `3` disclosed failure cases; provider and human evidence remain explicit limitations |
| IR-first Packaging | `openai`, `claude`, `generic`, and `vscode` adapters include compiler contracts, permission contracts, target-native behavior contracts, IR provenance, semantic parity checks, and install-scope notes where applicable |
| Context Budget | initial load `944/1000`, under the production budget |
| CI | `make ci-test` target count is `64` after the World-Class Evidence Ledger gate update |

## Next Highest-Leverage Moves

1. Deepen target-native behavior contracts into provider-native execution and provider-native installer integrations.
2. Add native client or installer runtime enforcement for approved high-permission capabilities.
3. Run the new provider-backed output runner against holdout cases with real credentials, then record the current blind A/B decisions before claiming fully ready status.
4. Add real reviewer annotation records during the next human review pass.
5. Install a real Browser/Chrome extension or provider client against `telemetry_native_host.py` and record production metadata events.
