[bilersan]

Summary

Closes #204

Adds first-class Google Antigravity (agy CLI and Antigravity IDE) integration to ctx as a peer to Claude Code, Codex, OpenCode, and Pi across four cohesive layers (AGY1–AGY4):

1. Unified Hook Protocol in ctx system ([AGY1]):

   • Auto-detects Antigravity camelCase stdin hook payloads (conversationId, workspacePaths, transcriptPath, modelName, lastUserInput, toolCall, error) in entity.HookInput while preserving 100% backward compatibility with Claude Code (snake_case).
   • Resolves workspacePaths[0] (including file:// URIs) and executes os.Chdir(ws) + rc.Reset() in session.ReadInput before state.Initialized() or rc.RC() runs so global/plugin hooks locate the workspace's .context/ and .ctxrc.
   • Emits Antigravity-compliant stdout JSON ({"decision":"allow"|"deny"}, {"injectSteps":[...]}, {}).
   • Bridges PreToolUse / PostToolUse nudges (qa-reminder, specs-nudge, post-commit, check-task-completion) into .context/state/agy-pending-<sessionID>.txt via QueuePendingAgy and flushes them as {"injectSteps":[...]} on the next PostInvocation (heartbeat) or PreInvocation (check-context-size) via FlushAgySteps.
   • Extends ScanTranscriptForTokens to sum input_tokens + cache_read_tokens on PLANNER_RESPONSE lines when scanning Antigravity transcript.jsonl files.

2. Embedded Antigravity Plugin Root & Skill Sync ([AGY2]):

   • Ships internal/assets/agy/ (plugin.json, hooks.json, mcp_config.json, rules/AGENTS.md, assets/logo.svg, and 50 skills/ctx-*/SKILL.md) embedded into the ctx binary.
   • Adds hack/sync-agy-skills.sh and make sync-agy-skills to mirror internal/assets/claude/skills/ and automatically split any SKILL.md body exceeding Antigravity's 24,000-byte limit (ctx-kb-ingest, ctx-architecture) into SKILL.md + references/details.md.
   • Validates cleanly under agy plugin validate internal/assets/agy --strict --json ("findings": []).

3. Project-Local Setup Deployer (ctx setup agy [--write]) ([AGY3]):

   • Adds internal/agy/ (Detect, PluginEnabled, MergeHooks, MergeMCP, SyncSkills) and internal/cli/setup/core/agy/ (Deploy, Preview).
   • Deploys .agents/hooks.json, ~/.gemini/config/mcp_config.json, AGENTS.md, and .agents/skills/, and short-circuits project-local hook/skill deployment when the global ctx@local-plugins plugin is enabled in ~/.gemini/antigravity-cli/settings.json to prevent duplicate hook execution.
   • Registers agy in steering.SyncTool (ConsumesDirectly polite skip for AGENTS.md), .ctxrc JSON schema, and CLI documentation (docs/cli/setup.md, docs/operations/integrations.md).

4. Session Transcript Parser (ctx journal import) ([AGY4]):

   • Adds internal/journal/parser/agy.go (Agy implementing Session) and registers ~/.gemini/antigravity-cli/brain in DefaultSessionDirs().
   • Parses transcript.jsonl (USER_INPUT and PLANNER_RESPONSE steps, stripping <USER_REQUEST>, <ADDITIONAL_METADATA>, and <SYSTEM_MESSAGE> wrappers, extracting thinking, tool calls, and token usage) while skipping transcript_full.jsonl duplicates.
   • Resolves session CWD via ~/.gemini/antigravity-cli/history.jsonl and documents Antigravity in docs/cli/journal.md.

Verification

• agy plugin validate internal/assets/agy --strict --json -> "findings": [] (50 skills, 1 hook config, 1 MCP server, 1 rule)
• go test ./internal/agy/... ./internal/cli/setup/core/agy/... ./internal/cli/system/... ./internal/assets ./internal/assets/read/skill/... ./internal/journal/parser/... ./internal/steering/... ./internal/entity/... ./internal/write/setup/... ./internal/compliance -run "TestShippedHooks|TestEveryDocPage|TestAgy"
• go test ./internal/audit -run "TestNoMixedVisibility|TestNoMagicStrings|TestNoDeadExports|TestDescKeyYAMLLinkage|TestTypeFileConvention|TestDocComments"