Detect Antigravity CLI and preserve interactive behavior

[Victor Vazquez (vhvb1989)]

Summary

• detect Google Antigravity CLI independently from Gemini using verified environment, user-agent, and exact process markers
• model agent interactive input and output capabilities separately so Antigravity keeps PTY prompts and terminal rendering
• fall back to automatic no-prompt mode when an Antigravity invocation does not have terminal input
• report Antigravity as a dedicated execution.environment telemetry value and synchronize telemetry documentation

Testing

• added unit coverage for Antigravity marker detection, precedence, false positives, process matching, capabilities, explicit overrides, and telemetry mapping
• verified targeted agent detection, terminal, command flag, telemetry resource, telemetry guard, build, and spelling checks
• locally validated the official Antigravity CLI 1.1.23 shell tool with offline azd env new, azd env select, and azd env remove prompts; text input, selection, confirmation, and terminal rendering completed without hangs, EOF, duplicated output, or lost responses

Antigravity is not installed or executed in CI. Live compatibility validation is local-only; CI coverage uses unit tests and mocked markers/capabilities.

Adding Antigravity is a new allowed value for the existing execution.environment field, not a new telemetry field or data classification.

Closes #9578

[github-actions]

📋 Prioritization Note

Thanks for the contribution! The linked issue isn't in the current milestone yet.
Thank you for logging this issue; our team is reviewing it. If you need urgent prioritization, tag Rick Winter (@RickWinter) and Kristen Womack (@kristenwomack) to let us know.

[azure-pipelines]

Azure Pipelines:
Successfully started running 1 pipeline(s).
21 pipeline(s) were filtered out due to trigger conditions.
There may be pipelines that require an authorized user to comment /azp run to run.

[Copilot]

🟡 Changes recommended

The telemetry privacy review is undocumented, and existing no-prompt help now contradicts the capability-aware behavior.

Once you've addressed the issues Copilot identified, you can request another Copilot review.

Pull request overview

Adds first-class Antigravity CLI detection while preserving its interactive terminal behavior and reporting dedicated telemetry.

Changes:

• Detects Antigravity through environment, user-agent, and process markers.
• Separates interactive input/output capabilities and adjusts no-prompt behavior.
• Updates tests and telemetry documentation.

File summaries

File	Description
docs/specs/metrics-audit/telemetry-schema.md	Adds the Antigravity telemetry value.
docs/specs/metrics-audit/feature-telemetry-matrix.md	Documents environment detection telemetry.
docs/reference/telemetry-data.md	Adds Antigravity to the public reference.
cli/azd/internal/tracing/resource/resource_test.go	Tests Antigravity telemetry mapping.
cli/azd/internal/tracing/resource/exec_environment.go	Maps Antigravity to its telemetry value.
cli/azd/internal/tracing/fields/fields.go	Defines the Antigravity environment constant.
cli/azd/internal/terminal/terminal.go	Separates input-terminal and output capabilities.
cli/azd/internal/terminal/terminal_test.go	Tests Antigravity TTY overrides.
cli/azd/internal/runcontext/agentdetect/types.go	Adds the agent type and capabilities.
cli/azd/internal/runcontext/agentdetect/detect_test.go	Covers markers, precedence, and false positives.
cli/azd/internal/runcontext/agentdetect/detect_process.go	Detects the exact agy process.
cli/azd/internal/runcontext/agentdetect/detect_env.go	Adds environment and user-agent markers.
cli/azd/docs/environment-variables.md	Documents markers and interactive behavior.
cli/azd/cmd/auto_install.go	Applies capability-aware no-prompt defaults.
cli/azd/cmd/auto_install_test.go	Tests defaults and explicit overrides.
cli/azd/cmd/auto_install_integration_test.go	Isolates Antigravity variables in tests.

Review details

• Files reviewed: 16/16 changed files
• Comments generated: 3
• Review effort level: Balanced

---

💡 Add a code-review agent skill or configure MCP servers for context-aware, tailored reviews. Learn more in the docs.

[JeffreyCA]

Thanks, I have a related change in #9818 to fix the terminal handling more generally

[JeffreyCA]

With #9818 merged, consider rebasing and keeping this PR focused on Antigravity detection, telemetry, and the live shell compatibility findings.

The SupportsInteractiveInput() and SupportsInteractiveOutput() gates would reintroduce the inherited-environment bug for other agents. A normal VS Code terminal launched from Claude Code still carries its markers, so these gates would disable prompts and rendering even when a human is using it.

• Remove the capability methods and gates. Keep the shared terminal.IsAttached check for physical stdin and stdout attachment, rather than introducing the stdin-only IsInputTerminal check. AZD_FORCE_TTY should remain a rendering override.
• Adapt the Antigravity tests to the existing descriptor-injection helpers, covering attached and detached invocations without using AZD_FORCE_TTY to simulate attachment.
• Add the Antigravity environment markers to pkg/azdext/tui.go so SDK detection stays aligned with core.

The marker detection, exact agy process matching, dedicated telemetry value, and live PTY findings still belong here.