Antigravity 2.17.0: Plan Before You Code

Google Antigravity has received its v2.17.0 update.

The guiding philosophy of this release is clear: "Plan before you build." From formalizing structured agent planning workflows to completely restructuring how rules occupy the model's context window, these changes directly target the pain points of complex software engineering.

Here is a summary of what's new 👇

1️⃣ Headline Feature: /plan — Review Before Writing Code

In complex engineering tasks, an agent making uncoordinated edits across an entire codebase can introduce regressions. Version 2.17.0 brings a disciplined workflow:

• Plan Review & Iteration: Triggering /plan prompts the agent to draft a comprehensive implementation design document first. You review and refine the proposal before code modification commences.
• Plan Review Policies: Select between three review policies in settings: review every plan, delegate review decisions to the agent based on critical seam thresholds, or bypass planning for simple one-off tasks.

2️⃣ Dedicated 20,000 Token Budget for Rules

Previously, extensive project guidelines risked crowding out Skills, Subagents, and MCP definitions within the limited active context window.

• Dedicated Rule Allocation: Project rules now enjoy an independent 20,000 token budget that does not compete with active conversational context.
• Graceful Fallbacks: Rules exceeding the budget automatically fold into compact "path + description" index stubs, dynamically fetched only when relevant.

3️⃣ Configuration Consolidation

• New Config Location: Workspace settings officially migrate to /.gemini/config.json.
• Deprecated Directory: The legacy .agents/settings.json file is no longer read. Custom paths such as personal_customization_dir should be migrated to the new file.

4️⃣ Quality of Life Enhancements

• Quick Theme Switching: Toggle dark/light themes directly from the Command Palette without opening the full Settings view.
• Custom Agent Hooks: Markdown agent specifications can now register lifecycle hooks in frontmatter via the hooks: property with relative and absolute path support.
• Paste Fidelity: Right-click paste supports rich text and images while preserving Markdown hyperlink formats; pasting over attachments no longer overwrites existing input text.
• Productized Command Surfaces: Slash commands and built-in Google plugins present official product branding and icons (e.g., Chrome DevTools, Gemini API) rather than raw internal identifiers.
• Quiet Links: Only actionable artifacts (such as newly created reviews or local dev servers) display interactive cards, while informational web lookups save quietly to sidebar history.
• Language Support: Added C++20 module interface (.cppm) syntax highlighting and icons.

5️⃣ Bug Fixes

• /rewind Snapshot Precision: Resolved an issue where rewinds selected outdated historical snapshots; rollbacks now strictly target the latest state preceding the selected checkpoint.
• Large File & Diff Responsiveness: Syntax highlighting and diff computations moved off the UI main thread; files exceeding 100 KB gracefully fallback to plain text to preserve fluidity.
• Large Repo Timeout Prevention: Extended custom rule and workflow discovery timeouts from 3s to 15s to eliminate false-negative loading failures in large monorepos.
• /btw Context Preservation: Interleaved side-queries now maintain the active subagent profile rather than resetting to the root agent.
• Math Formula Rendering: Fixed rendering artifacts where inline math containers with $$ caused dropped text or stray dollar symbols.
• Media Asset Export: Addressed silent failures when saving SVGs and encoded video streams.

💡 Summary

Antigravity 2.17.0 represents a mature step forward in agentic engineering discipline: establishing a formal planning phase with /plan and decoupling rule tokens from execution context.

If you are using Antigravity on medium to large codebases, upgrading is strongly recommended!