The Rust Agent tool only persisted queued metadata, so delegated work never actually ran. This change wires Agent into a detached background conversation path with isolated runtime, API client, session state, restricted tool subsets, and file-backed lifecycle/result updates.
Constraint: Keep the tool entrypoint in the tools crate and avoid copying the upstream TypeScript implementation
Rejected: Spawn an external claw process | less aligned with the requested in-process runtime/client design
Rejected: Leave execution in the CLI crate only | would keep tools::Agent as a metadata-only stub
Confidence: medium
Scope-risk: moderate
Reversibility: clean
Directive: Tool subset mappings are curated guardrails; revisit them before enabling recursive Agent access or richer agent definitions
Tested: cargo build --release --manifest-path rust/Cargo.toml
Tested: cargo test --manifest-path rust/Cargo.toml
Not-tested: Live end-to-end background sub-agent run against Anthropic API credentials
The Agent tool previously stopped at queued handoff metadata, so this change runs a real nested conversation, preserves artifact output, and guards recursion depth. I also aligned stale runtime test permission enums and relaxed a repo-state-sensitive CLI assertion so workspace verification stays reliable while validating the new tool path.
Constraint: Reuse existing runtime conversation abstractions without introducing a new orchestration service
Constraint: Child agent execution must preserve the same tool surface while preventing unbounded nesting
Rejected: Shell out to the CLI binary for child execution | brittle process coupling and weaker testability
Rejected: Leave Agent as metadata-only handoff | does not satisfy requested sub-agent orchestration behavior
Confidence: high
Scope-risk: moderate
Reversibility: clean
Directive: Keep Agent recursion limits enforced wherever nested Agent calls can re-enter the tool executor
Tested: cargo fmt --all --manifest-path rust/Cargo.toml; cargo test --manifest-path rust/Cargo.toml; cargo clippy --manifest-path rust/Cargo.toml --workspace --all-targets -- -D warnings
Not-tested: Live Anthropic-backed child agent execution against production credentials
Implement the first web-oriented Claude Code parity slice in the Rust tools crate. This adds concrete WebFetch and WebSearch tool specs, execution paths, lightweight HTML/search-result extraction, domain filtering, and local HTTP-backed tests while leaving the existing core file and shell tools intact.\n\nConstraint: Keep the change scoped to tools-only Rust workspace code\nConstraint: Match Claude Code tool names and JSON schemas closely enough for parity work\nRejected: Stub-only tool registrations | would not materially expand beyond MVP\nRejected: Full browser/search service integration | too large for this first logical slice\nConfidence: medium\nScope-risk: moderate\nReversibility: clean\nDirective: Treat these web helpers as a parity foundation; refine result quality without renaming the exposed tool contracts\nTested: cargo fmt; cargo test -p tools\nNot-tested: cargo clippy; full workspace cargo test
Wire the CLI to the Anthropic client, runtime conversation loop, and MVP in-tree tool executor so prompt mode and the default REPL both execute real turns instead of scaffold-only commands.
Constraint: Proxy auth uses ANTHROPIC_AUTH_TOKEN as the primary x-api-key source and may stream extra usage fields
Constraint: Must preserve existing scaffold commands while enabling real prompt and REPL flows
Rejected: Keep prompt mode on the old scaffold path | does not satisfy end-to-end CLI requirement
Rejected: Depend solely on raw SSE message_stop from proxy | proxy/event differences required tolerant parsing plus fallback handling
Confidence: medium
Scope-risk: moderate
Reversibility: clean
Directive: Keep prompt mode tool-free unless the one-shot path is explicitly expanded and reverified against the proxy
Tested: cargo test -p api; cargo test -p tools; cargo test -p runtime; cargo test -p rusty-claude-cli; cargo build; cargo run -p rusty-claude-cli -- prompt "say hello"; printf '/quit\n' | cargo run -p rusty-claude-cli --
Not-tested: Full interactive tool_use roundtrip against the proxy in REPL mode
