Compatibility

Compatibility

Hosts and surfaces Crickets is verified to run with.

Supported hosts

Crickets customizations declare host compatibility per-manifest via the YAML supported_hosts: field. The installer reads that field and dispatches the customization to the right host-specific path.

Host	Path convention	Status
Claude Code (Anthropic CLI / IDE extension)	.claude/{skills,agents,hooks,commands}/<name>/	✅ first-class — primary development surface, CI-verified on every push
Antigravity 2.0 (Google IDE) + Antigravity CLI (agy)	.agents/{skills,workflows,rules}/<name>/ (project) + ~/.gemini/config/plugins/<name>/ (user-global, plugin-wrapped)	✅ first-class as of v1.2.0 — CI-verified on every push. Migrated from .agent/ (singular) to .agents/ (plural) in v1.2.0 per ADR 0011. Antigravity CLI replaced Gemini CLI 2026-05-19; consumer Gemini CLI sunsets 2026-06-18.

See Per-Host-Paths for the full per-kind destination matrix.

Supported operating systems

OS	Tested via	Frequency
Linux (ubuntu-latest)	.github/workflows/tests-linux.yml	Every push + every PR
macOS (macos-latest)	.github/workflows/tests-mac.yml	Every push + every PR
Windows (windows-latest, PowerShell 7+)	.github/workflows/tests-windows.yml	Every push + every PR

The single aggregate CI badge in the README + wiki Home points at a dedicated ci-all.yml workflow that waits for all 3 OS workflows then reports a combined success/failure. Diagnostic drill-down: click the badge → Actions tab → pick the OS that's failing.

Per-customization compatibility

Each customization in the shipped catalog declares its own supported_hosts in the manifest:

Kind	Customization	Hosts
skill (2)	pii-scrubber, dependabot-fixer	[claude-code, antigravity]
agent (2)	evaluator, diataxis-evaluator	[claude-code, antigravity] (sub-agent-as-skill on Antigravity)
hook (3)	kill-switch, steer, commit-on-stop	[claude-code] (Antigravity hook-surface support tracked separately — see Known gaps below)
bundle (2)	quality-gates (claude-code-only because contents include hooks), example-bundle ([claude-code, antigravity])	inherits from contents
plugin (1)	example-plugin (reference; Antigravity 2.0 + agy)	[antigravity]

The installer respects each manifest's supported_hosts — installing into a target project only writes the customizations declared for the host(s) you're targeting.

Hook host-effectiveness matrix

A hook can be emitted on a host without being effective there. Antigravity runs plugin hooks observe / side-effect-only — it fires them but ignores their exit codes and never reads their stdout. So a hook that vetoes a tool call or injects steering text is inert on Antigravity even though it runs. The matrix below is the effectiveness contract for the crickets hooks as shipped in v3.0:

Hook	Plugin	Claude Code	Antigravity	Why
commit-on-stop	developer-safety	✅ effective	✅ effective	Pure side-effect (it commits) — needs no exit-code/stdout contract, so it works on both hosts.
kill-switch	developer-safety	✅ effective	⚠️ fires but advisory only	Vetoes via non-zero exit; Antigravity ignores exit codes, so the veto doesn't block.
steer	developer-safety	✅ effective	⚠️ fires but advisory only	Injects via stdout; Antigravity never reads hook stdout, so the steer text is dropped.
evidence-tracker	code-review	✅ effective	❌ not effective	Its enforcement/veto needs the hook-veto contract Antigravity lacks; Claude-only (supported_hosts: [claude-code]).
harness-context	developer-workflows	✅ effective	❌ not emitted	SessionStart hook; Claude-only — Antigravity has no SessionStart hook surface.

Rule of thumb: side-effect-only hooks port to both hosts; any hook whose value depends on its exit code (veto) or stdout (inject) is Claude-only-effective. See Develop a crickets plugin locally and ADR 0009 for the underlying host contracts.

Snippet emission

The snippet kind is an instruction fragment. The generator emits it as an Antigravity rules/ file (<plugin>/rules/<name>.md) and drops it on Claude Code — Claude Code's plugin surface has no instruction-file primitive to land it in. So developer-safety's commit-no-coauthor + worktrees-never-auto conventions ship as Antigravity rules but have no Claude-Code emitted form. See Per-Host Paths and Customization Types for the per-kind detail.

Known gaps — Antigravity 2.0 surface

Three Antigravity 2.0 primitive surfaces have no file-based authoring path as of crickets v1.2.0. Customizations targeting these surfaces are out of scope for the crickets installer; users must hand-author them in a Python SDK environment if they want to use them.

Hooks gap

Antigravity 2.0 / agy hooks are Python decorators registered at agent-creation time via LocalAgentConfig(hooks=[...]) (from google.antigravity.hooks). The 9 hook types (on_session_start, on_session_end, pre_turn, post_turn, pre_tool_call_decide, post_tool_call, on_tool_error, on_compaction, on_interaction) cover most use cases that Claude Code's file-based hooks cover, but they require Python SDK integration to register — no .agents/hooks/ directory or hooks.json config file exists.

Crickets ships four hooks (kill-switch / steer / commit-on-stop in developer-safety; evidence-tracker in code-review) plus the harness-context SessionStart hook in developer-workflows. As of crickets v3.0 the evidence-tracker hook ships into crickets (code-review plugin), Claude-only — its enforcement/veto needs the Claude-Code hook-veto contract that Antigravity lacks. (The memory recall hooks remain agentm-native, not crickets.) See the Hook host-effectiveness matrix below for which hooks are effective on which host. See ADR 0009 § Antigravity re-audit outcome for the original rationale — its "no Antigravity file-based hook surface" finding is superseded by Antigravity 2.0 (tracked in the crickets-ADR-overhaul follow-up).

Future direction (deferred, FOLLOWUP candidate): a separate Python sidecar package (crickets-hooks-py?) could translate crickets's file-based hook scripts to SDK decorator registration at agent-author boot time. Out of scope for v1.2.0.

Note

Gotcha for hook authors — resolve the workspace from the host's hook-input contract, never from cwd. A bash hook that checks .harness/… (or any project-relative path) relative to cwd works on Claude Code but is silently inert on Antigravity, because the two hosts invoke plugin hooks differently:

• Claude Code — runs hooks with cwd = the project root, and also supplies it on stdin (cwd) and via $CLAUDE_PROJECT_DIR.
• Antigravity / agy — runs plugin hooks with cwd = the plugin dir (not the workspace), and supplies the workspace only on stdin as JSON {"workspacePaths":["<root>"]} (no env var).

A host-portable hook reads stdin, parses it with a real JSON parser (python3 json.load, top-level keys only — a sed/regex parser mismatches nested or pretty-printed payloads), and resolves the root as workspacePaths[0] (Antigravity) → stdin cwd (Claude) → $CLAUDE_PROJECT_DIR → cwd (fallback), then cds into it before any relative logic. The shipped kill-switch, steer, and commit-on-stop hooks do this; see scripts/test_developer_hooks_workspace.py for the contract cases. (Fixed crickets v3.0 #40 part 6 T2; full plugin-authoring treatment lands in the upcoming "Develop a crickets plugin locally" how-to + ADR 0013/0014.)

Scheduled tasks (triggers) gap

Antigravity 2.0 / agy triggers — the host's scheduled-task primitive — are Python registration patterns: every(seconds, callback), on_file_change(path, callback), custom async functions. Registered via LocalAgentConfig(triggers=[...]). No file-based config; trigger callbacks are Python code running in the agent process.

Crickets doesn't ship trigger primitives in v1.2.0. The Agent M V7 roadmap (agentm/.harness/ROADMAP-AgentMemoryV7.md) contemplates a scheduled-sidecar framework as a future cross-host primitive; if/when that lands, it may also provide an Antigravity-trigger integration path. See agentm V7 for forward-looking context. (This was the V6/dream-mode roadmap before the 2026-06-03 V5-unbundling arc renumber.)

Multi-agent orchestration gap

Antigravity 2.0's multi-agent orchestration is operator-facing: the parent agent decides when to spawn subagents via the built-in start_subagent tool, enabled by default via CapabilitiesConfig(enable_subagents=True). No plugin-author surface for orchestration policy (which subagents to spawn, when, with what context).

Crickets's contribution to orchestration is the sub-agent-as-skill pattern: ship SKILL.md files (via kind: agent or kind: plugin); the parent agent treats them as callable sub-agents via start_subagent. The agents-available-for-spawning surface is what crickets controls; the spawning decisions are the parent agent's.

Deeper orchestration design (e.g. specifying spawn policy via manifest fields) would require a customization kind we don't yet have — and unclear value vs. letting the parent agent reason about it dynamically. Out of scope.

Sibling repo

Crickets pairs with Agent M (agentm) — the structural backend harness (phase-gated workflow, auto-recall, on-disk state). Agent M is tested on the same OS matrix; both repos ship paired releases per ADR 0006.

Out-of-scope hosts

Hosts that previously had adapters or were considered but are not supported now:

• Gemini CLI — dropped in v0.9.0 (2026-05-17). Google replaced Gemini CLI with the new Antigravity CLI (agy) on 2026-05-19; consumer Gemini CLI sunsets 2026-06-18 (transition blog). Enterprise tier keeps Gemini CLI indefinitely (out of scope for crickets). Antigravity CLI IS supported as of crickets v1.2.0 (shares the agent harness with Antigravity 2.0 desktop; single antigravity slug).
• Codex — never had a Crickets adapter; was dropped from the harness in v1.0.0 per harness ADR 0005.

When a host stops working

If a host's CI starts failing or a customization's adapter goes stale:

1. Check the host's release notes for surface changes (.claude/ shape, .agent/ shape, command syntax, etc.)
2. Verify the affected customization's manifest supported_hosts field still matches reality
3. Run bash scripts/smoke-install-bash.sh locally; if it fails on the affected host, you've reproduced
4. Patch the installer dispatch logic OR the customization's manifest, whichever resolves the surface change at the right layer

For adding new hosts, see ADR 0006 — Split customizations into crickets for the customization contract + Manifest-Schema for the per-customization declaration shape.