Host Adapter Matrix

Better Harness runs inside your existing coding agent. Host differences enter only a thin adapter layer: host shells, configured-asset providers, session evidence adapters, and output modes. Canonical product judgment stays host-neutral.

Support levels

Better Harness currently declares ten more complete capability-level host adapters, a partial Augment/Auggie session-only adapter, plus bounded DSH discovery, configured-assets, and session slices. Six have verified public Quickstart paths. Pi, Kimi Code, WorkBuddy, and Grok are visible as adapter support because their installation and end-to-end evidence boundaries differ from that six-host set. DSH has Verified install/discovery for a qualified runtime/preset boundary plus developer-preview configured-assets and session-evidence contracts. It supports shared read-only Asset Practices, neutral Harness analysis, Evidence Bundles, and qualified portable HTML durable output. The canonical adapter matrix remains the complete capability-level source of truth.

Supported host adapters

Host	Public entry	Positioning	Shell	Session Evidence	Default Output
Qoder	Verified Quickstart	First-class product host	.qoder-plugin/	Qoder sessions	Qoder Canvas report
Claude Code	Verified Quickstart	Analysis-capable source-local host	.claude-plugin/	Workspace-matching local Claude transcripts when present	Self-contained HTML + Markdown
Augment/Auggie	Partial adapter	Session evidence only; no install or configured-asset claim	None	Workspace-qualified local Augment JSON sessions with usage, context windows, and explicit history-summary boundaries	Harness Inspector self-contained HTML
Codex	Verified Quickstart	Analysis-capable source-local host	.codex-plugin/	Codex sessions	Self-contained HTML + Markdown
Cursor	Verified Quickstart	Canvas-capable source-local host	.cursor-plugin/	Workspace-matched transcripts, metadata, audit logs, and optional native Context Usage snapshots; partial coverage stays explicit	Cursor Canvas report
Qwen Code	Verified Quickstart	Analysis-capable source-local host	qwen-extension.json	Workspace-matching local Qwen transcripts when present	Self-contained HTML + Markdown
GitHub Copilot	Verified Quickstart	Analysis-capable source-local host	.github/plugin/	Workspace-matched Copilot CLI transcripts; partial coverage stays explicit	Self-contained HTML + Markdown
Pi	Adapter support	Analysis-capable source-local host	pi manifest in package.json	Workspace-matching local Pi sessions, including the Oh My Pi (OMP) session layout	Self-contained HTML + Markdown
Kimi Code	Adapter support	Analysis-capable source-local host	.kimi-plugin/plugin.json	Workspace-matching Kimi wire transcripts	Self-contained HTML + Markdown
WorkBuddy	Adapter support	Analysis-capable source-local host	None; skills use WorkBuddy-owned paths	Workspace-matching WorkBuddy JSONL transcripts	Self-contained HTML + Markdown
Grok	Adapter support	Analysis-capable source-local host	None; skills use Grok-owned paths	Workspace-matching Grok session dirs (updates.jsonl)	Self-contained HTML + Markdown
DeepSeek Harness (DSH)	Verified install/discovery	Qualified headless/base and Web standard/code/cordis; shared read-only analysis over partial configured-assets and session evidence	Local DSH Cordis policy; no lifecycle shell	DSH JSONL backend session format 0: raw .jsonl and feature-detected .jsonl.zstd	Self-contained HTML + Markdown

The @qoder-ai/better-harness npm package includes all seven plugin metadata roots. Pi reuses install metadata in the existing package.json, so it does not add an eighth filesystem metadata root. The generated Qoder runtime bundle includes only the Qoder shell; non-Qoder generated host artifacts remain source-local.

Read-only plugin lifecycle

The standalone CLI can normalize local Better Harness installation evidence without flattening host capability differences:

better-harness plugin status --host all
better-harness plugin verify --host all
better-harness doctor --platform all

plugin plan requires one explicit host and emits typed native argv or manual steps without executing them. Qoder Desktop remains bundled, Codex Desktop uses manual UI steps, Cursor installation stays unavailable while its local help contract is stale, persistent Pi operations without native evidence stay unavailable, transient Pi update/remove are not applicable, and WorkBuddy returns PLUGIN_LIFECYCLE_UNSUPPORTED. Kimi Code and Grok have no validated native lifecycle contract yet, so lifecycle targets reject them with UNKNOWN_HOST while their adapter evidence stays available. DSH likewise has no lifecycle profile: lifecycle targets reject it with UNKNOWN_HOST; its manually configured verified discovery and partial session evidence remain available. The shadow host profiles do not replace the canonical adapter matrix while ADR-0002 remains proposed. DSH's verified discovery does not add a lifecycle target.

Output modes

• Qoder Canvas — renderer-owned findings.json, Canvas-only canvas.json, and report.canvas.tsx.
• Cursor Canvas — the same complete report contract rendered with cursor/canvas, native Context Window evidence, and IDE actions.
• HTML visual — portable Claude Code/Codex/Qwen/Copilot/Pi/Kimi Code/WorkBuddy/Grok/DeepSeek Harness contract covering findings.json, report.md, and a self-contained report.html (see the sample report).
• Markdown-only — no visual companion.

DSH reuses the portable html mode to publish findings.json, report.md, and report.html at the generic Better Harness-owned root <target>/.dsh/better-harness. That root is not a native DSH storage contract. This qualification adds neither Canvas, Checkup, Studio, nor a claim of full DSH support.

Adapter support boundaries

Augment/Auggie

Augment support is intentionally limited to read-only local Session evidence. session-analysis --platform augment reads bounded JSON sessions from ~/.augment/sessions or an explicit --augment-home; Harness Inspector uses the default local root through that shared adapter. Admission uses recorded IDE workspace folders, repository roots, or terminal cwd; titles and prompt text are never workspace identity. Usage nodes retain input, output, cache-read, and cache-creation lanes, derive prompt occupancy from those additive lanes, and use same-response max_context_tokens only when observed. Native history_summary_node records are explicit compaction boundaries, while an unmarked context shrink remains only a measured shrink.

This slice was checked against local Auggie 0.36.0. It does not provide an Augment shell, installation route, configured-asset inventory, lifecycle target, generic Harness renderer, Evidence Bundle, model attribution, or parent/subagent inference, and it is not a public Quickstart.

Pi

Pi can install the repository through pi install <source> or load it with pi -e <source>. Lifecycle status treats persisted user/project package settings as the cli inventory surface and one-run pi -e activation as the separate cli-session session-only surface; empty settings do not prove that a running session omitted the package. Package discovery, configured assets, workspace-matched session evidence, and portable HTML routing are implemented. Pi remains outside the verified Quickstart set until a complete interactive report-loop smoke is observed.

Oh My Pi (OMP)

Oh My Pi (OMP) is not a separate host adapter: it is a session layout the pi platform recognizes when PI_CODING_AGENT_DIR=~/.omp/agent points at an OMP agent directory. OMP has no host id, capability profile, install shell, or lifecycle target of its own.

OMP keys session directories on the home-relative workspace path (~/src/dotai → -src-dotai) instead of pi's absolute --<slug>-- form, and its JSONL transcripts start with a title record before the session header. The Pi adapter reads both naming conventions and skips that preamble while keeping pi's fail-closed header rule and workspace isolation. An OMP /fork transcript copies its parent's entries; those entries count as the parent's only when the parent session is discovered in the same result, so nothing is double-counted and nothing silently disappears. Session evidence and portable HTML routing come from the shared Pi provider, and configured assets are inventoried by the Pi provider because it honors the same PI_CODING_AGENT_DIR override.

Kimi Code

Kimi Code installs the repository through /plugins install <source> and the .kimi-plugin/plugin.json manifest, then invokes /skill:better-harness after reload. Configured assets, workspace-matched wire transcripts, and portable HTML routing are implemented. Kimi Code remains outside the verified Quickstart set until a complete interactive report-loop smoke is observed.

WorkBuddy

WorkBuddy configured assets, workspace-matched session evidence, and portable HTML routing are implemented. This repository does not ship a WorkBuddy install shell, plugin manifest, or npm-packaged host artifact; installation remains on WorkBuddy's own ~/.workbuddy/skills or marketplace surfaces.

Grok

Grok configured assets, workspace-matched session evidence, and portable HTML routing are implemented. This repository does not ship a Grok install shell or npm-packaged host artifact; installation is a manual skill symlink into ~/.grok/skills/better-harness (or project .grok/skills). Grok remains outside the verified Quickstart set until a complete interactive report-loop smoke is observed.

DeepSeek Harness (DSH)

DSH has Verified install/discovery against DSH 0.1.1-rc.2 at audited source b150a551b8d465e31e418e1b2eaf5e79bbb7d28e. The only supported route points the active skill-filesystem.customSkillDirs at the absolute <BETTER_HARNESS_ROOT>/skills directory and loads the Better Harness DSH policy from the same complete root. The policy fails closed unless DSH's winning definition has the expected custom source, SKILL.md path, directory resourceBase, two-parent root, and required root resources. A direct user /better-harness gesture then injects the canonical Skill at DSH's pre-model step boundary, while a model-facing Better Harness skill tool call is rejected.

This route is qualified for headless/base. In Web it is qualified only for an active user preset copied from standard, code, or cordis and configured through that preset's scoped skill-filesystem row. Web minimal has no Skill loader and remains unsupported. DSH's project-local same-name roots keep their native higher precedence, but such a winner is reported unverified rather than canonical. Standalone copies and symlinks/junctions are not supported install routes. Paths must be absolute; DSH resolves relative paths from its process working directory and does not expand a literal ~. Moving the complete Better Harness root requires reconfiguring every absolute path. The Installation page documents the configuration boundary; run the pinned, credential-free owner smoke with npm run test:dsh-native.

DSH also has a developer-preview configured-assets provider. It reports native filesystem Skill winners and cwd-sensitive Instruction sources as configured-not-observed evidence:

better-harness agent-customize inventory --provider dsh --workspace <path> [--cwd <path>] [--dsh-home <dir>] [--include-user-home[=true]]

User-home Skills and Instructions are not read by default. Runtime/in-process Skills and active Cordis, Profile, and Preset composition remain unresolved. The host advertises exactly sessionAnalysis, agentCustomize, assetPractices, harnessReport, reportRendering, and evidenceBundle. Shared analysis freezes canonical --cwd for current configured practice while leaving historical Session scope unchanged. Durable output reuses the existing portable renderer; explicit inline/no-files operation remains write-free. Checkup, Canvas, Studio, and public Quickstart support remain unavailable. Repository contributors can run the pinned credential-free comparison with npm run test:dsh-configured-assets-native. See DeepSeek Harness Configured Assets.

Separately, DSH has a developer-preview JSONL session slice with Better Harness adapter metadata dsh-v1. Its format-0 session-evidence slice is validated against DSH dsh-v0.1.0-rc.7 and dsh-v0.1.0-rc.8, including RC8 interrupted assistant messages and required team-event vocabulary. Team events are validated and accounted, not projected as team analytics. Home resolution is strictly --dsh-home over DSH_HOME over ~/.dsh; the only source root is <home>/sessions. The adapter reads the fixed nested session.jsonl or session.jsonl.zstd layout without writing or repairing artifacts, and it qualifies a workspace only from the header's absolute cwd.

Compressed artifacts are concatenated independently checksummed Zstandard frames and are validated and decompressed one complete frame at a time. The public API available in supported Node.js 22.20 and 24 runtimes is feature-detected. When it is unavailable, including Node.js 23.0 through 23.7, compressed evidence is reported unavailable while independent raw JSONL evidence remains readable; no fallback dependency is installed. Known-but-unsupported and unknown ignorable events are accounted for, while unknown required events, committed corruption, identity drift, and unsupported versions fail closed. Uncommitted final raw rows and structurally incomplete final Zstandard frames preserve only the prior committed prefix and remain incomplete. The adapter does not infer plugin ownership, causality, or faults.

The implemented source-checkout smoke boundary is read-only:

node scripts/session-analysis.mjs sources --platform dsh --workspace <path> [--dsh-home <dir>]

Qualified portable output does not imply complete native DSH integration. DSH has no live PTY/process integration, complete runtime configured-asset resolution, plugin lifecycle, managed shell, manifest, package integration, Canvas, Checkup, Studio, public Quickstart, SQLite or custom persistence support, automatic optimization, plugin-fault attribution, or mutation/recovery of native DSH Session sources, Skills, Instructions, or configuration/state. Better Harness-owned findings.json, report.md, and report.html remain managed under <target>/.dsh/better-harness by the generic portable publication and rollback contract. See the canonical source matrix and Story #93.

Capability coverage

Capabilities differ per host on purpose: no host claims a capability without a real evidence source, and unsupported behavior fails before reading private data or changing files. The maintained capability-by-capability coverage table, TODO list, and definition of done live in the repository roadmap.

Source of truth

The canonical matrix, discovery rules, and split triggers live in docs/adapters/README.md.

Contributing another host

Start with Contributing a Coding Agent Host. It separates native shell, configured-asset, session, output, and packaging claims and links Qwen Code and GitHub Copilot pull requests as worked examples.