We built a source-available LLM reliability library (free for research / personal / internal eval) that can cut inference cost by half at matched quality, and you adopt it by changing one import [P] [R]

TL;DR: Reliability techniques (methods that boost an LLM's correctness by spending extra inference, e.g., retries with feedback, ensembling, generator/critic refinement, verification passes, difficulty-aware routing) are scattered across the literature, each in its own paper-specific codebase. We unified 28 reliability techniques ( 21 communication-theoretic methods across 6 families plus 7 prior-method baselines : Self-Consistency, Self-Refine, CoVe, BoN, Weighted BoN, CISC, MoA), each measured against an uncoded single-pass baseline, under a single API, with 3 adaptive routers (SemKNN + two local ACM routers) sitting on top, then showed that routing the technique adaptively per prompt lets you slide along a quality/cost frontier. In our paper benchmark with one specific lineup, Nemotron + Devstral as the two generators and GLM-5.1 as the judge, the adaptive router delivered ~56% cost reduction at matched quality, or ~7% quality bump at matched cost, vs the best fixed method we compared against at that same lineup. One knob ( λ ) does the sliding. The qualitative pattern (adaptive beats fixed) should generalize, but absolute numbers are lineup-specific, and we haven't run the full sweep across other model combinations yet. Adoption is change one import : python - from openai import OpenAI + from agentcodec.openai import OpenAI Pass reliability="harq_ir" (or any of the 28 techniques) and existing client.chat.completions.create(...) calls keep their native OpenAI response shape. Same drop-in shims for Anthropic and Ollama. GitHub: https://github.com/intellerce/agentcodec Working paper: https://arxiv.org/abs/2605.09121 After spending a while researching reliability methods from papers, we kept hitting the same wall: every paper ships its own one-off codebase with its own prompt format, its own scoring rubric, its own model wrapper. Benchmarking "should we use self-refine or best-of-N here?" turned into a week of plumbing per comparison. The communication-theory framing is what tied it together: an LLM is a stochastic channel Y = A(X) + N , and every reliability technique from the wireless world has a direct analog in agent-land : Wireless Agent-land ARQ / HARQ retry-with-feedback loops Diversity combining (MRC/SC/EGC) ensemble multiple models Turbo decoding iterative generator/critic mutual refinement Fountain codes rateless sampling, stop when the judge is confident FEC answer + structured parity passes (re-derivation, verification, alternative), decode by cross-check ACM (adaptive coding-modulation) route by difficulty We put all of them in one library: 28 reliability techniques (the 7 prior-method baselines are part of that 28, not on top of it), plus the uncoded single-pass baseline they're all measured against, plus 3 adaptive routers (SemKNN + two local ACM routers) that select a technique per prompt. Full breakdown in the README. The minimal version ```python from agentcodec import ReliabilityModule mod = ReliabilityModule.from_dict({ "models": [ # Spatial diversity: two different families = uncorrelated errors {"model": "qwen3:8b", "base_url": "http://localhost:11434/v1", "api_key": "ollama"}, {"model": "llama3.1:8b", "base_url": "http://localhost:11434/v1", "api_key": "ollama"}, ], "judge": {"model": "gemma3:12b", "base_url": "http://localhost:11434/v1", "api_key": "ollama"}, "critic": {"same": True}, "strategy": {"type": "fixed", "technique": "harq_ir", "params": {"max_rounds": 4}}, }) result = mod.run("Prove the sum of the first n odd integers is n 2.", category="reasoning") print(result.text, result.cost_usd, result.cost_source, result.technique_used) ``` Swap "harq_ir" for "diversity_mrc" , "turbo" , "fountain" , etc. Same API, same ReliabilityResult shape, same cost-source tier on every output. For production, flip strategy to routed and the library picks the technique per prompt (cheap baseline on easy prompts, diversity_mrc on hard ones). Three things worth calling out Beyond the technique catalog, three pieces of the implementation that took real work: 1. Native async streaming for all but 2 techniques ( acm_soft , acm_learned ), with role-tagged events. mod.astream() drives AsyncOpenAI / AsyncAnthropic / httpx.AsyncClient end-to-end (no worker-thread bridge) and emits TokenEvents tagged with a role: "answer" , "thinking" , "draft" , "critique" , "verification" , "candidate" , "synthesis" . So when you stream a HARQ-IR run, you can render the round-by-round drafts and critiques live, not just the final answer: python async for ev in mod.astream("Explain QUIC vs TCP."): if isinstance(ev, TokenEvent): if ev.role == "answer": print(ev.text, end="", flush=True) elif ev.role == "draft": print(f"\n[draft] {ev.text}") elif ev.role == "critique": print(f"\n[CRITIC] {ev.text}") elif ev.role == "thinking": pass # captured to result.thinking_text elif isinstance(ev, FinalEvent): print(f"\ndone — {ev.result.technique_used}, " f"thinking_cost=${ev.result.thinking_cost_usd:.4f}") Parallel-branch techniques