feat(policy): Implement Tool Annotation Matching in Policy Engine

[jerop]

Fixes #20025
Follow up on #20024

• Add toolAnnotations field to PolicyRule and SafetyCheckerRule types.
• Implement partial record matching for toolAnnotations in the policy engine.
• Update check and checkShellCommand to propagate annotations during evaluation.
• Update TOML loader to support parsing toolAnnotations from policy files.
• Add comprehensive unit and integration tests for behavior-based security rules using readOnlyHint.

Note: Future work will implement the pipeline to capture and propagate annotations from discovered MCP servers as part of #19655.

[gemini-code-assist]

Summary of Changes

Hello @jerop, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request significantly enhances the policy engine by introducing support for tool annotations. This new feature allows policy rules to be defined and enforced based on metadata associated with tools, such as a readOnlyHint. By propagating these annotations through the policy evaluation process and enabling their parsing from TOML configuration, the system gains a more flexible and powerful mechanism for security and behavior-based policy enforcement.

Highlights

• Tool Annotation Support: Introduced a toolAnnotations field to PolicyRule and SafetyCheckerRule types, enabling policies to be defined based on tool metadata.
• Policy Engine Matching Logic: Implemented partial record matching for toolAnnotations within the policy engine, allowing for more granular control over tool execution based on their metadata.
• Annotation Propagation: Updated the check and checkShellCommand methods to correctly propagate toolAnnotations during the policy evaluation process.
• TOML Loader Enhancement: Enhanced the TOML policy loader to support parsing toolAnnotations from policy configuration files.
• Comprehensive Testing: Added extensive unit and integration tests to validate the new annotation matching behavior and ensure its correctness.

Changelog

• packages/cli/src/config/policy-engine.integration.test.ts
  • Added an integration test case to verify that the policy engine correctly matches rules based on toolAnnotations.
• packages/core/src/policy/policy-engine.test.ts
  • Added unit tests to confirm that the policy engine can match tools by semantic annotations and supports scoped annotation rules.
• packages/core/src/policy/policy-engine.ts
  • Modified the ruleMatches function to incorporate toolAnnotations in the rule matching logic.
  • Updated the check and checkShellCommand methods to accept and pass toolAnnotations during policy evaluation.
• packages/core/src/policy/toml-loader.test.ts
  • Added a test to ensure that toolAnnotations are correctly parsed from TOML policy files.
• packages/core/src/policy/toml-loader.ts
  • Extended PolicyRuleSchema and SafetyCheckerRuleSchema to include an optional toolAnnotations field.
  • Modified the loadPoliciesFromToml function to properly load toolAnnotations into policy rules.
• packages/core/src/policy/types.ts
  • Added the toolAnnotations property to the PolicyRule and SafetyCheckerRule interfaces.

Activity

• No specific activity (comments, reviews, or progress updates) has been recorded for this pull request since its creation.

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[gemini-code-assist]

Code Review

The pull request introduces tool annotation matching to the policy engine, allowing for more granular control over tool execution based on metadata. This is a significant improvement for defining behavior-based security rules. The changes include updating policy types, implementing the matching logic, and propagating annotations through methods. Additionally, the TOML loader has been updated to support parsing toolAnnotations from policy files, and tests have been added to validate the new functionality. The code is well-tested and adheres to the project's architectural guidelines.

[github-actions]

Size Change: +852 B (0%)

Total Size: 25.7 MB

ℹ️ View Unchanged

Filename	Size	Change
./bundle/gemini.js	25.2 MB	+852 B (0%)
./bundle/node_modules/@google/gemini-cli-devtools/dist/client/main.js	221 kB	0 B
./bundle/node_modules/@google/gemini-cli-devtools/dist/src/_client-assets.js	227 kB	0 B
./bundle/node_modules/@google/gemini-cli-devtools/dist/src/index.js	11.5 kB	0 B
./bundle/node_modules/@google/gemini-cli-devtools/dist/src/types.js	132 B	0 B
./bundle/sandbox-macos-permissive-open.sb	890 B	0 B
./bundle/sandbox-macos-permissive-proxied.sb	1.31 kB	0 B
./bundle/sandbox-macos-restrictive-open.sb	3.36 kB	0 B
./bundle/sandbox-macos-restrictive-proxied.sb	3.56 kB	0 B
./bundle/sandbox-macos-strict-open.sb	4.82 kB	0 B
./bundle/sandbox-macos-strict-proxied.sb	5.02 kB	0 B

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