Effective Harnesses for Long-Running Agents - Anthropic Engineering
Claude Agent SDK Overview - Anthropic Platform
New Patterns:
One Feature at a Time (Rule #7 in Core Autonomy)
Work on exactly one feature per iteration
Complete, commit, verify before moving to next
Prevents over-commitment and ensures clean progress tracking
E2E Browser Testing with Playwright MCP
Features NOT complete until verified via browser automation
New Essential Pattern: Playwright MCP -> Automate browser -> Verify UI features visually
Detailed verification flow added to SKILL.md
Note: Playwright cannot detect browser-native alert modals
Advanced Task Tool Parameters
run_in_background: Returns output_file path, output truncated to 30K chars
resume: Continue interrupted agents with full context
Use cases: Context limits, rate limits, multi-session work
Fixed
Release workflow: Use gh CLI instead of softprops action for atomic release creation
Comments
[2.35.0] - 2026-01-08 Added - Anthropic Agent Harness Patterns & Claude Agent SDK Sources:
Effective Harnesses for Long-Running Agents - Anthropic Engineering Claude Agent SDK Overview - Anthropic Platform New Patterns:
One Feature at a Time (Rule #7 in Core Autonomy)
Work on exactly one feature per iteration Complete, commit, verify before moving to next Prevents over-commitment and ensures clean progress tracking E2E Browser Testing with Playwright MCP
Features NOT complete until verified via browser automation New Essential Pattern: Playwright MCP -> Automate browser -> Verify UI features visually Detailed verification flow added to SKILL.md Note: Playwright cannot detect browser-native alert modals Advanced Task Tool Parameters
run_in_background: Returns output_file path, output truncated to 30K chars resume: Continue interrupted agents with full context Use cases: Context limits, rate limits, multi-session work Fixed Release workflow: Use gh CLI instead of softprops action for atomic release creation