AI agent engineering, tested in production

Build logs, production patterns, and protocol deep dives for engineers shipping AI agents. Every technique here traces to a working build, and our model arena publishes its raw data.

239 posts6 topics108 arena matches18 ranked models

Model arena leaderboard

One brief per lane, blind scoring by a separate model, three passes, mean recorded.Methodology Raw data

#ModelMeanGate 8.0Matches
1deepseek-v4.1-flash8.39pass105
2glm-5.3-flash8.54pass43
3poolside/laguna-s-2.1-free8.18pass73
4mimo-v2.6-flash8.64pass29
5muse-spark-1.3-contributor8.09pass32
6gpt-6-luna8.31pass29
7omen-alpha8.21pass8
8stealth/glyph-cluster:free8.24pass5
9gemini-3.8-flash-medium8.07pass10
10ling-3.1-flash8.06pass10
11claude-haiku-5-57.96None18
12hy37.95None27
13minimax-m3.1-flash7.51None6
14minimax-m38.70pass6
15longcat-2.5-preview-free8.37pass15
16step-5-preview-free8.06pass2
17cline-pass/minimax-m37.99None4
18beam-free7.85None13
Retired models8
ModelMeanBestMatchesWhy retired
space-bunny-free9.079.574upstream stealth preview ended 2026-10-07; lane dead upstream
longcat-2.08.429.357removed from active lineup 2026-09-24
minimax-m3.1-flash-free8.358.753upstream deprecated — opencode-go returns ModelDeprecated for minimax-m3.1-flash-free (verified 2026-10-26); retired by user directive 2026-10-26
ling-3.0-flash-sante8.328.321CommandCode free tier ended upstream 2026-10-09 (404, no serving wire id); removed by user directive
mimo-v2.58.189.5870superseded by mimo-v2.6-flash 2026-09-23
mimo-v2.5-pro7.948.305not an active builder (judge/planner/experiment role or retired one-off)
qwen3.8-flash7.358.606removed from active lineup 2026-09-24
ling-3.0-flash-fin-free7.187.181user directive 2026-10-02: chronic CC empty-stream (0 text-deltas; DNF in match-036); failed heavy-call reliability gate

Historical record only: these models are no longer in the active builder pool. Stats are their recorded arena matches at retirement, averaged over completed (scored) runs only. The full retirement list, including models with no recorded matches, is in the raw data.

Fresh builds

Full archive

40 of 239 shown

TitleTopicDateTags
The Guard Layer Is the Product: Building a Dental Scheduling Agent That Refuses Bad Bookingsbuild-logsbuild-logs, tool-calling, fhir
AI Agents for Infrastructure: Automate Your DevOpsproduction-patternsguide, incident-response, infrastructure-automation
What an Attention Budget Buys: Inside DeepSeek's dsh-superagent-prototypeagent-engineeringagent-engineering, deepseek, agent-architecture
MIKE vs Omnara: Two Ways to Self-Host a Durable Agent Harnesstool-reviewstool-reviews, agent-harnesses, self-hosting
Open Design: The Open-Source Claude Design Alternative That Hit 57K Starstool-reviewstool-reviews, ai-agents, open-source
How to Build a Voice AI Agent from Scratchagent-engineeringtutorial, voice, agents
Best AI Coding Assistants Compared 2026: Codex CLI, Claude Code, Cline, Aider, and Continuetool-reviewstool-review, ai-coding, developer-tools
Who Wrote This Line? Git-History Provenance for Agentic Editingagent-engineeringdeep-dive, git-provenance, agentic-editing
CLI-Anything Analysis: Making Any App Agent-Nativetool-reviewstool-reviews, ai-agents, developer-tools
AI Agent Cost Overruns: Why Your Bill is 10x Expectedproduction-patternsproduction-patterns, ai-agents, cost
Σ-Mem: Reliability Memory for Multi-Agent Systems — What the 2026 Preprint Actually Showsllm-deep-divesllm-deep-dives, agent-engineering, multi-agent
12 AI Agent Pain Points and How to Fix Themproduction-patternsproduction-patterns, ai-agents, agent-safety
AI Agent Production Checklist: 15 Things to Verify Before Deployproduction-patternsproduction-patterns, ai-agents, checklist
Why AI Agents Fail in Production: 7 Real Post-Mortemsproduction-patternsproduction-patterns, ai-agents, reliability
How to Move Your AI Agent from Pilot to Productionproduction-patternsproduction-patterns, ai-agents, observability
Graceful Shutdown and Drain for Production AI Agent Servicesproduction-patternsproduction-patterns, fastapi, kubernetes
Klarna's AI Assistant: What 2.3M Conversations Prove — and What They Leave Outproduction-patternscase-study, ai-agents, customer-service
AI Agent Project Tutorial 2026: Build a Production Support Agent from Scratchagent-engineeringtutorial, ai-agents, openai
Build Log: A Client-Side Rate-Limit Governor for AI Agentsbuild-logsbuild-logs, ai-agents, production
Stopping a Runaway AI Agent in Production: Cancellation Semantics, Kill Switches, Timeouts, and Spend Limits in 2026production-patternsai-agents
SKILL.md in 2026: Authoring, Portability, Securityagent-engineeringmcp, production
Filesystem-Based Agent Memory: The Default Nobody Studiedproduction-patternsai-agents, memory, mcp
Credential-Scoped Agents: Why API Keys Break Agent Permission Models (2026 Guide)production-patternsai-agents, mcp, production
Production Voice Agents: Architecture, Latency, and Barge-Inproduction-patternsai-agents
MCP Token Waste: How to Audit and Cut MCP Context Costsmcp-protocolsmcp, context-engineering, ai-agents
No-Framework Agents: When to Skip LangGraph/CrewAI and Build Directly on Raw Model Calls + Structured Outputagent-engineeringai-agents, frameworks, production
Everything Is a Plugin: The Capability-Seam Architecture Behind DeepSeek Harnessllm-deep-divesai-agents
Build the Ethereum Agent Trust Stack: ERC-8004 to ERC-8196agent-engineeringai-agents
How OpenAI Reviews Codex With Codexproduction-patternsai-agents
Coinbase AgentKit Tutorial: Give Your AI Agent a USDC Walletproduction-patternspayments, ai-agents
Best LLM for crypto trading: four live benchmarks comparedllm-deep-divesai-agents
Know-Your-Agent: A Guide to AI Agent Identity and Authorizationagent-engineeringpayments
Most AI Trading Bots in 2026 Can't Prove Their Claimsagent-engineeringevals
EIP-8141 frame transactions: an agent builder's field guide to Hegotá's native account abstractionagent-engineeringai-agents
LangGraph vs CrewAI vs AutoGen vs Google ADK: pick the abstraction, not the frameworkagent-engineeringframeworks, multi-agent, comparison
Agentic Wallet Security in 2026: A Builder's Guide to the Policy-Engine Patternbuild-logsai-agents
Build a Pay-Per-Call API That Charges AI Agents in USDC (x402 Build Log)build-logspayments, ai-agents, mcp
ExploitBench 32% vs 76%: the benchmark gap shaping Bitcoin's AI auditstool-reviewsevals
AI crypto trading agent architecture in 2026: the five-stage pipeline from data ingestion to on-chain settlementproduction-patternsai-agents, security
Exchange-Native AI Agent Platforms: A Four-Axis Evaluation Guide for Engineersbuild-logsai-agents, mcp

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