feat(capability): Phase 3 - corvus-composer with AgentManifest schema

[yacosta738]

Summary

Implements Phase 3A (Agent Manifest) and Phase 3B (AgentComposer) of the capability-based architecture.

What Changed

• Created crates/corvus-composer/ with:

  • AgentManifest TOML schema (serializable Rust structs with serde)
  • Validation rules per PRD (R1-R7):
    • R1: At least one provider required
    • R2: At least one channel required
    • R3: Default provider must be enabled
    • R4: Enabled capabilities must be known
    • R5: Memory backend must be valid
    • R6: Security sandbox must be valid
    • R7: Tool restrictions must be subset of enabled tools
  • ValidationError enum for structured errors
  • CapabilityReport for introspection via required_capabilities()
  • Known capability registries (providers, channels, tools, backends)

• Implements AgentComposer that:

  • Parses manifests from TOML string or file path
  • Validates against PRD requirements
  • Provides required_capabilities() returning CapabilityReport
  • Provides validate_with_warnings() for non-blocking issues
  • Provides into_agent_builder() placeholder (delegates to bootstrap)

• Added crate to workspace (Cargo.toml) and wired into main corvus crate (lib.rs)

Not Changed

• Existing AgentBuilder (kept as low-level assembly interface)
• CLI commands (deferred to Phase 4)
• .claude/ directory

Tests

All 8 corvus-composer tests pass:

• parse_minimal_manifest
• validate_requires_providers
• validate_requires_channels
• validate_requires_default_in_providers
• validate_unknown_provider
• validate_tool_restrictions_subset
• required_capabilities
• warnings_for_empty_tools

Validation

• cargo fmt --check ✅
• cargo clippy ✅
• cargo test -p corvus-composer ✅ (8 tests)
• cargo test ✅ (3478 tests)

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📝 Walkthrough

Walkthrough

This PR establishes a modular trait abstraction layer by creating seven new workspace crates (corvus-traits, corvus-providers, corvus-channels, corvus-tools, corvus-memory, corvus-security, corvus-composer) that extract core runtime traits and types from the monolithic agent-runtime crate. The main runtime crate and existing modules are refactored to re-export from the extracted crates. A new TOML-driven agent manifest composition system (corvus-composer) is introduced for declarative agent configuration and validation.

Changes

Cohort / File(s)	Summary
Core Trait Infrastructure (corvus-traits) crates/corvus-traits/Cargo.toml, crates/corvus-traits/src/lib.rs, crates/corvus-traits/src/channels.rs, crates/corvus-traits/src/memory.rs, crates/corvus-traits/src/multimedia.rs, crates/corvus-traits/src/providers.rs, crates/corvus-traits/src/security.rs, crates/corvus-traits/src/tools.rs, crates/corvus-traits/src/testing.rs	New core trait definitions for channels (multimodal messaging), memory (session/entry storage), multimedia (image/audio metadata), providers (LLM chat abstraction), security (sandbox isolation), and tools (function calling). Introduces comprehensive APIs with serializable data structures and async trait methods.
Registry/Wrapper Crates crates/corvus-providers/Cargo.toml, crates/corvus-providers/src/lib.rs, crates/corvus-channels/Cargo.toml, crates/corvus-channels/src/lib.rs, crates/corvus-memory/Cargo.toml, crates/corvus-memory/src/lib.rs, crates/corvus-security/Cargo.toml, crates/corvus-security/src/lib.rs, crates/corvus-tools/Cargo.toml, crates/corvus-tools/src/lib.rs	New public registry crates that re-export corvus-traits types and provide metadata structs (ProviderInfo, ChannelInfo, MemoryInfo, SecurityInfo, ToolInfo) for capability discovery.
Agent Composition Framework crates/corvus-composer/Cargo.toml, crates/corvus-composer/src/lib.rs	New TOML manifest schema (AgentManifest) with sections for providers, channels, tools, memory, observer, and security. Includes AgentComposer for TOML/file parsing, validation (required capabilities, defaults, known provider/channel/tool/backend validation), warnings (empty tools, missing memory), and trait-object builder placeholder. Extensive test coverage for parsing, validation failures, and capability reporting.
Workspace and Root Updates Cargo.toml, src/lib.rs	Updated workspace members list to include all new corvus-* crates. Added new public composer module to main runtime re-exporting corvus-composer. Updated root Cargo.toml dependencies on new internal crates.
Media Type Refactoring src/channels/media.rs, src/channels/audio_media.rs	Removed local definitions of AllowedImageMime, ImageTransportForm, StagedImage, and ImageHistoryMeta (and audio equivalents); replaced with corvus-traits::multimedia re-exports. Added centralized cleanup_staged_image() helper function to replace per-type cleanup methods. Updated callsites in mod.rs, discord.rs, slack.rs to use shared cleanup.
Trait Re-export Refactoring src/channels/traits.rs, src/memory/traits.rs, src/providers/traits.rs, src/tools/traits.rs, src/security/traits.rs	Converted all trait definition files from containing full implementations to thin re-export shims importing from corvus-traits. Removed ~2,700 lines of local implementations (trait methods, helpers, test modules) now owned by extracted crates.
Test and Adapter Updates src/providers/reliable.rs, src/providers/router.rs, tests/traits_api_compat.rs	Added compatibility wrapper types (ModelAwareMockHandle, MockProviderHandle) in provider tests to maintain boxed trait objects. New 380-line integration test validating type identity and trait object interchangeability between legacy and extracted trait paths via dummy implementations.

Sequence Diagram

sequenceDiagram
    participant User
    participant AgentComposer as Agent Composer
    participant Validator as Validator
    participant Report as Capability Report
    participant Builder as Agent Builder

    User->>AgentComposer: from_toml(manifest_str)
    AgentComposer->>Validator: validate()
    Validator->>Validator: Check required providers/channels
    Validator->>Validator: Verify defaults exist & enabled
    Validator->>Validator: Validate against KNOWN_* lists
    Validator->>Validator: Check sandbox/memory backends
    Validator->>Validator: Verify tool_restrictions ⊆ enabled tools
    Validator-->>AgentComposer: Result<(), ValidationError>
    AgentComposer->>Report: populate_from_manifest()
    AgentComposer-->>User: AgentComposer { manifest, reports }
    User->>AgentComposer: into_agent_builder()
    AgentComposer->>Builder: new() with capabilities
    Builder-->>User: Result<B>

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Estimated code review effort

🎯 4 (Complex) | ⏱️ ~75 minutes

Possibly related PRs

• corvus#510: Direct predecessor/parallel refactor extracting identical trait infrastructure into corvus-traits workspace crates with matching module structure and re-export patterns.
• corvus#68: Adds MemoryValidationResult and Memory::validate_response method that are now part of the extracted corvus-traits::memory module.
• corvus#182: Extends ToolResult with a new structured field for JSON payloads, which is now defined in the extracted corvus-traits::tools module.

Suggested labels

area:rust, area:docs, risk:high

Suggested reviewers

• yuniel-acosta

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title follows Conventional Commit style with 'feat(capability):' prefix, clearly describes the Phase 3 implementation with AgentManifest schema, and is 69 characters (within the 72-character limit).
Description check	✅ Passed	The PR description comprehensively covers Summary, What Changed (with detailed subsections), Not Changed, Tests (with specific test names), and Validation (with tool outputs). It closely follows the template structure and provides actionable detail for review.
Docstring Coverage	✅ Passed	Docstring coverage is 85.71% which is sufficient. The required threshold is 80.00%.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch feature/capability-architecture-480-composer

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[github-actions]

✅ Contributor Report

User: @yacosta738
Status: Passed (12/13 metrics passed)

Metric	Description	Value	Threshold	Status
PR Merge Rate	PRs merged vs closed	89%	>= 30%	✅
Repo Quality	Repos with ≥100 stars	0	>= 0	✅
Positive Reactions	Positive reactions received	10	>= 1	✅
Negative Reactions	Negative reactions received	0	<= 5	✅
Account Age	GitHub account age	3087 days	>= 30 days	✅
Activity Consistency	Regular activity over time	108%	>= 0%	✅
Issue Engagement	Issues with community engagement	0	>= 0	✅
Code Reviews	Code reviews given to others	545	>= 0	✅
Merger Diversity	Unique maintainers who merged PRs	2	>= 0	✅
Repo History Merge Rate	Merge rate in this repo	92%	>= 0%	✅
Repo History Min PRs	Previous PRs in this repo	230	>= 0	✅
Profile Completeness	Profile richness (bio, followers)	90	>= 0	✅
Suspicious Patterns	Spam-like activity detection	1	N/A	❌

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_{Contributor Report evaluates based on public GitHub activity. Analysis period: 2025-04-11 to 2026-04-11}

[sonarqubecloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud