Tutorials Intermediate
Claude Code Mods: Build a Fail-Closed Bash Guard in JS
Write a Claude Code mod that blocks, asks, and logs risky shell commands, then test it.
16 min read·Kodetra Technologies
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AI Guides for Builders
How-to content for builders, indie hackers, and AI engineers. Less theory, more shipped code.
Tutorials 
Tutorials Intermediate
Claude 950-Agent Swarm: Build a Funnel in Python
Rebuild the 21-hour enzyme-hunt pattern: cheap triage, deep read, budget cap, resumable.
11 min read·Kodetra Technologies
7d ago
Tutorials Intermediate
Sonnet 5.5 Drops tool_choice: Build a Strict Tool Router
Forced tool use now 400s on Claude Sonnet 5.5. Replace it with strict tools and a retry guard.
9 min read·Kodetra Technologies
8d ago
Tutorials Intermediate
Claude Code Projects: Retire an API Across 3 Repos
Set up Claude Code's new Projects beta to run coordinated, parallel AI coding threads across repos.
11 min read·Kodetra Technologies
10d ago
Tutorials Intermediate
Opus 5.5 Progress Updates: Stop Silent Agent Turns
Opus 5.5 moved agent narration into thinking blocks. Stream it back with display updates and nudges.
15 min read·Kodetra Technologies
12d ago
Tutorials Advanced
Opus 5.5 Background Compaction: Agents That Never Stall
Summarize long Claude Opus 5.5 sessions in a background thread and swap the result in, no pause.
15 min read·Kodetra Technologies
13d ago
Tutorials Intermediate
Opus 5.5 Upgrade: Fix 4 Breaking Changes Before They 400
Opus 5.5 is 20% cheaper, but old thinking, tool_choice and computer-use code now fails. Fix it.
15 min read·Kodetra Technologies
13d ago
Tutorials Intermediate
Anthropic SDK v1.0: The Silent httpx2 Mock Trap
Upgrade to anthropic>=1 without your respx mocks and OTel traces going quietly blind.
13 min read·Kodetra Technologies
Aug 26
Tutorials Advanced
Claude Browser Toolset: Ref Targeting Over Pixels
Wire browser_toolset_20260801 to Playwright: ref targeting, batched turns, halt-on-failure.
15 min read·Kodetra Technologies
Aug 21
Tutorials Intermediate
Claude Skills API Is GA: Ship a Versioned Skill
Upload, version and pin a custom Agent Skill on the Claude API now that /v1/skills is GA.
12 min read·Kodetra Technologies
Aug 20
Tutorials Intermediate
Claude Code Subagents: Build a Parallel Review Fleet
Define custom .claude/agents specialists and fan them out in parallel to review code.
11 min read·Kodetra Technologies
Aug 12
Tutorials Intermediate
Drop-In Claude Swap: DeepSeek via the Anthropic SDK
Run your Claude Messages API code on DeepSeek V4-Pro by changing one base URL.
9 min read·Kodetra Technologies
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