AI Coding Benchmarks Explained: SWE-bench, LiveBench, and More

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OpenHands Team

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Any given week in 2026, a different model tops a different coding leaderboard. One chart declares a new state of the art, another shows the same model several points lower, and a vendor deck cites a number nobody outside the company can reproduce. Each figure is usually accurate on its own terms, because each one measures something different under different rules.

You need to understand those rules before benchmark scores can help you choose an AI coding agent for your team. This guide covers what AI coding benchmarks measure, the nine benchmarks worth knowing in 2026, why their scores disagree, and how to run your own evaluation on the work your team does.

What are AI coding benchmarks?

An AI coding benchmark is a standardized test that measures how well a model or agent completes software engineering tasks. Every benchmark, whatever its reputation, combines the same three parts:

  • Task set: The work the system is asked to do, from short synthetic Python functions to real GitHub issues paired with the pull requests that fixed them.

  • Evaluation setup: The conditions the system solves the task under, including the system prompt, tools, retrieval, execution environment, and retry logic.

  • Scoring method: The definition of success, whether hidden tests, objective ground-truth answers, or blind human votes.

The most useful distinction is model benchmark versus agent benchmark. A model benchmark measures a large language model (LLM) in isolation, with a prompt in and an answer out, no file system, no terminal, and no retry loop. An agent benchmark measures the full working loop, where the system searches a repository, edits files, runs tests, reads failures, and revises its patch before submitting.

That difference is why a score on an agent benchmark belongs to the whole system, the model plus the scaffold wrapped around it. A model that completes isolated functions well is not automatically good at fixing a real GitHub issue, and an agent that resolves issues well may owe part of its score to retrieval, retry logic, and tool orchestration specific to its harness.

Why engineering teams follow AI coding benchmarks

Benchmarks give you an independent yardstick in a market where the leading coding model changes every few weeks. Vendor launch posts always show a win, and a public benchmark with a disclosed setup is the quickest way to check whether that win holds up under neutral conditions. Trackers like the SWE-bench leaderboard republish results under consistent rules, which makes real trends visible across model generations.

Following them helps in three specific ways. A leaderboard can narrow twenty candidate models to three worth testing before you spend a token. Score-versus-cost data helps you set budgets, since an agent that resolves tasks at a tenth of the price changes the math on automation. Saturation is useful information too, since a task set every leading model clears can no longer separate them.

The 9 AI coding benchmarks worth knowing in 2026

These nine benchmarks span the range from single-function checks to full agentic evaluations. The table compares them on five factors, and each entry below opens with what the benchmark tests.

BenchmarkWhat it testsTask typeHow it's scoredContamination riskUse it for
SWE-bench VerifiedFixing real GitHub issuesAgentic, single public repoFail-to-pass test suitesHigh, public and saturatingIssue-resolution signal
SWE-bench ProHarder, longer-horizon issue resolutionAgentic, multi-file, held-out and commercial reposPass@1 under a unified scaffoldLower by design, task quality under auditDifficulty reality check
SWE-rebenchFreshly mined issue resolutionAgentic, monthly-refreshed public reposFail-to-pass tests, pass@1 and pass@5Low, time-split monthly refreshDecontaminated issue signal
Terminal-BenchShell use and environment managementAgentic, sandboxed terminal tasksHidden tests per task, multiple attemptsMedium, public but versionedCommand-line and ops capability
Aider PolyglotMulti-language code editingSingle-file exercises, six languagesTest pass rate after up to two attemptsMedium, public Exercism problemsInexpensive editing-regression check
LiveBenchCoding, agentic coding, reasoningMixed, rotating monthlyObjective ground truth, no LLM judgeLow, delayed question releaseContamination-resistant signal
Chatbot ArenaHuman preference on answersOpen-ended, head-to-headBlind pairwise votes, Bradley-Terry modelLow, live promptsPreference signal
HumanEval and MBPPSingle-function completionSingle-step, synthetic PythonPass@k against test casesHigh, saturatedFloor check
OpenHands IndexFive software engineering task areasAgentic, composite workloadAbility, cost, and runtime per categoryMedium, mixed public setsWorkload-mix comparison

1. SWE-bench Verified

SWE-bench Verified tests whether an agent can fix real GitHub issues. The set holds 500 human-validated instances selected by OpenAI and the original SWE-bench authors from open-source Python projects.

  • Task type: Agentic and scoped to a single public repository, where the agent works against real code until it produces a patch.

  • How it's scored: Fail-to-pass test suites, so a submitted patch counts only when it makes the repository's failing tests pass.

  • Contamination risk: High, since the issues and their fixes are public. Top models cluster above 80%, with the public leaderboard putting the newest models in the low-to-mid 90s% as of July 2026.

  • Use it for: An issue-resolution signal, not a complete measure of production readiness.

Most of the coding scores quoted in model launch posts come from this benchmark. Its age and visibility are also why it saturated first.

2. SWE-bench Pro

Scale AI built SWE-bench Pro as a harder version of the same idea. It tests longer-horizon issue resolution across 1,865 problems in 41 repositories, and the leading models evaluated in the original paper stayed below 25%, with the top at 23.3%.

  • Task type: Agentic and multi-file, spanning public, held-out, and commercial codebases built to resist training exposure.

  • How it's scored: Pass@1 under a unified scaffold, which reduces scaffold variation but it doesn’t eliminate it.

  • Contamination risk: Lower by design, though an OpenAI audit found roughly 30% of the public split's tasks broken as of July 2026, so rising Pro scores deserve caution.

  • Use it for: A difficulty reality check on how far saturated leaderboard scores transfer to harder enterprise-style work.

Watching how far a model falls from Verified to Pro shows you how much of its score depends on familiar public code.

3. SWE-rebench

SWE-rebench keeps SWE-bench's real GitHub issue format but rebuilds its test set every month, drawing on an automated pipeline that has mined more than 21,000 decontaminated tasks from active open-source repositories.

  • Task type: Agentic and scoped to real Python repositories, with each monthly batch collected from issues opened in the prior month so the tasks stay unseen.

  • How it's scored: Fail-to-pass test suites reported as pass@1 and pass@5, run under a fixed scaffold that isolates the model's own contribution.

  • Contamination risk: Low by construction, since a time-based split scores each model only on issues created after its training cutoff.

  • Use it for: A decontaminated issue-resolution signal when you want SWE-bench's format without its saturation.

Because the tasks are mined automatically rather than hand-curated for solvability, resolved rates run below SWE-bench Verified, with the leading models in the mid-60s% on recent monthly sets as of July 2026. Tracking one model across successive batches shows whether a score reflects capability or exposure.

4. Terminal-Bench

Terminal-Bench tests whether an agent can operate a real command-line environment, and its current 2.0 set holds 89 tasks across 16 categories spanning software engineering, system administration, data processing, and security.

  • Task type: Agentic and sandboxed, where each task ships as its own container the agent must navigate, configure, and drive to a working end state.

  • How it's scored: Hidden tests check each task against a human-written solution, averaged over several attempts per task for a fractional success rate.

  • Contamination risk: Medium, since the tasks are public, though the bespoke environments and periodic version bumps limit straight memorization.

  • Use it for: A read on shell fluency and environment management, the setup friction that repository benchmarks skip.

Top harnesses now reach the low-to-mid 80s% on the 2.0 set as of July 2026. The score rewards agents that can install dependencies, manage processes, and recover from a broken shell, not only edit files.

5. Aider Polyglot

Aider Polyglot tests precise code editing across languages, drawing on 225 of the hardest Exercism exercises in C++, Go, Java, JavaScript, Python, and Rust.

  • Task type: Single-file exercises with one described function to complete, repeated across six languages rather than Python alone.

  • How it's scored: Unit-test pass rate after up to two attempts, with the model required to return changes in a structured diff or whole-file edit format that applies cleanly.

  • Contamination risk: Medium, since the Exercism problems are public, though the six-language spread makes rote memorization less useful than on single-language sets.

  • Use it for: An inexpensive check on editing precision and regressions, since the suite is cheap to run and reports cost alongside accuracy.

The strongest models now reach the high 80s% as of July 2026, and the share of well-formed edits matters as much as the raw pass rate. A model that writes correct logic but malformed diffs will regress on real edits no unit test would catch.

6. LiveBench

LiveBench is built to avoid the contamination problem. It tests coding, agentic coding, and reasoning through roughly 21 tasks across seven categories as of July 2026.

  • Task type: Mixed and rotating monthly, with new questions held private for a month before release.

  • How it's scored: Objective ground truth with no LLM judge, which removes grader bias along with memorization.

  • Contamination risk: Low by construction, since models cannot have trained on questions that did not exist.

  • Use it for: A contamination-resistant directional signal when comparing models across coding and reasoning work.

The tradeoff is breadth, since only part of the suite is coding-specific. You'll get more from the coding and agentic coding categories than from the overall average.

7. Chatbot Arena

Chatbot Arena measures human preference instead of test results, and it now operates as LMArena, with a dedicated code leaderboard and a WebDev Arena for building web apps.

  • Task type: Open-ended head-to-head comparisons, where people see two anonymous answers to the same prompt.

  • How it's scored: Blind pairwise votes, aggregated through a Bradley-Terry model into a ranking.

  • Contamination risk: Low, because prompts arrive live, though verbosity, style, and formatting can sway votes in ways unit tests never would.

  • Use it for: A preference signal, not proof that a model ships correct code.

Developer preference still carries real information, since clear explanations matter in daily work. It complements execution-based benchmarks rather than replacing them.

8. HumanEval and MBPP

HumanEval and MBPP are the two classic function-completion benchmarks, and both now work mainly as floor checks. HumanEval is OpenAI's 2021 set of 164 hand-written Python problems, and MBPP, short for Mostly Basic Python Problems, adds 974 crowd-sourced problems from Google Research, 427 of them in a hand-verified sanitized subset. Each one asks a model to complete a single Python function from a short description.

  • Task type: Single-step synthetic Python, one described function at a time, with no tools or repository context.

  • How it's scored: Pass@k against the benchmark's test cases, the share of problems solved within k sampled attempts.

  • Contamination risk: High and fully saturated, with today's top models routinely clearing 90% on both.

  • Use them for: A floor check, where a weak score is a warning and a strong score proves little about repository-level work.

Their 2021-era designs predate coding agents entirely, so they say nothing about tool use or repositories, though MBPP's larger problem count gives the steadier of the two numbers. The scores still appear on most model cards, which makes their limits worth knowing, and neither one should drive a buying decision in 2026.

9. OpenHands Index

The OpenHands Index measures a broader mix of work than any single benchmark above. Published by OpenHands, it tests agents across five software engineering areas, covering issue resolution, greenfield development, frontend work, software testing, and information gathering.

  • Task type: Agentic and composite, built from SWE-bench Verified, Commit0, SWE-bench Multimodal, SWT-Bench, and GAIA.

  • How it's scored: Ability, cost, and runtime per category, rather than one collapsed accuracy number.

  • Contamination risk: Medium, since some component sets are public.

  • Use it for: Choosing a model for a specific workload mix and budget instead of chasing a headline score.

Unlike most benchmark leaderboards, the OpenHands Index reports ability, runtime, and cost together, making it useful when evaluating tradeoffs across different software engineering workloads.

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Why benchmark scores disagree with each other

Benchmarks disagree first because they measure different things. A SWE-bench Verified score reflects an agent patching a real Python issue inside a prepared Docker environment, a HumanEval score reflects one completed function, an LMArena ranking reflects which answer people preferred, and an internal vendor benchmark reflects a custom scaffold nobody outside can reproduce. Two of those numbers can move in opposite directions without either one being wrong.

Setup moves the number even within one benchmark. Anthropic reported Claude 3.7 Sonnet moving from 62.3% to 70.3% on SWE-bench Verified with a custom scaffold, and GPT-4o ranged from 23% to 33.2% across scaffolds in OpenAI's own analysis. Epoch AI's benchmarking analysis found scaffold choice the single biggest factor in overall performance, worth 11 to 15 points for recent top models.

Contamination, saturation, and cost account for the rest. Public task sets leak into training data, so gains start reflecting exposure instead of capability, which is why OpenAI stopped evaluating SWE-bench Verified in early 2026. The replacement did not hold up either, since OpenAI walked back its SWE-bench Pro recommendation in July 2026 after an audit found roughly 30% of the public split's tasks broken. Cost rounds out the list, and Princeton's AI Agents That Matter research argues accuracy-only evaluation rewards needlessly expensive agents, so every published score is a claim about one specific setup at one point in time.

No single benchmark measures every aspect of software engineering. Repository issue resolution, terminal usage, code editing, reasoning, cost, latency, and human preference all capture different capabilities. Rather than searching for a universal leaderboard, engineering teams should combine multiple public benchmarks that reflect the types of work they expect agents to perform.

What AI coding benchmarks leave out

Even a well-run benchmark measures a narrow slice of engineering. Six production dimensions rarely show up in a leaderboard number:

  • Multi-file and multi-repo coordination: Many benchmark tasks are scoped to a single repository and a well-defined issue. Production work often spans services, packages, schemas, tests, documentation, and deployment configuration, and dependency upgrades or migrations frequently need coordination across many repositories. If your real work is multi-repo, do not assume a single-repo score will transfer.

  • Long-horizon execution and failure recovery: A task that completes in minutes says nothing about behavior over hours. Longer runs give agents room to drift, chase a wrong assumption, or compound an early mistake, so recovery deserves its own evaluation.

  • Repository setup and environment friction: Benchmarks run in prepared environments. Your codebase probably has internal packages, private registries, custom continuous integration (CI), secrets, and non-standard builds, and an agent can fail before it ever reaches the code change.

  • Cost per resolved task: Token price is not task cost. Retries, long contexts, failed attempts, and human follow-up all count, so track spend per accepted change rather than per token.

  • Auditability and governance: A leaderboard says nothing about who triggered an agent, what it accessed, or why a reviewer should trust the output. Platform and security teams need visibility into the run itself before agents touch production code.

  • Human review burden: An agent can raise throughput while flooding your reviewers. Output only counts when your team can review and merge it, and benchmarks rarely measure the cleanup a patch requires.

These dimensions decide whether agent output ships, so teams that evaluate agents seriously use public scores only as a first filter.

Most public benchmarks evaluate whether an agent can complete a task. Engineering teams also need to evaluate how that work gets done. Does the agent recover from failed tests? How many retries does it need? How much human cleanup is required? What did the run cost? Could another engineer understand why it made each change?

Those workflow questions often determine whether an agent succeeds in production, even when two systems post similar benchmark scores.

How to read published benchmark results

Seven questions separate a meaningful score from a marketing number. Each one takes seconds to check against a published result:

  1. What benchmark is it? A HumanEval score, a SWE-bench score, and an internal vendor number measure different things.

  2. Is it a model or an agent result? When tools, retrieval, and retries were involved, the score belongs to the whole scaffold.

  3. What was the evaluation setup? A score without the prompt, tools, environment, and retry policy attached is incomplete.

  4. How recent is it? Models and scaffolds move fast enough that a six-month-old score can mislead.

  5. Is the benchmark contaminated or saturated? Public static datasets lose signal as training exposure grows.

  6. What did it cost? Accuracy without cost hides agents too expensive to run at scale.

  7. How close is it to your workload? A narrow issue-resolution score is one input when your work is migrations, testing, or frontend.

A result that holds up under all seven questions is worth acting on. Most results fail one or two, and it helps to know exactly which ones.

How to run your own AI coding benchmark

The best benchmark is the one you run on your own codebase, and six steps are enough to set one up:

  1. Real tasks first: Choose recent bugs, dependency updates, test generation, or small features your team understands well, with real CI and review consequences attached.

  2. Identical instructions: Run every tool with the same prompt, so you compare agent behavior instead of input quality.

  3. Outcome tracking: Record task success, cost per task, latency, number of attempts, test regressions, and human-review acceptance for every run.

  4. Side-effect review: Check whether the agent touched unnecessary files, broke adjacent workflows, or ignored your internal conventions.

  5. Failure recovery: Hand the agent a failing test or a misleading stack trace, then watch whether it recovers, asks for help, or compounds the mistake.

  6. Repeat runs, untrusted review: Outputs vary across runs, so run each task more than once, review patches like code from an unknown contractor, and keep humans responsible for merge decisions.

The goal is not to reproduce a public leaderboard. You are answering a narrower question, whether this agent can do your work, in your environment, under your constraints.

Evaluate agents on the work that matters

The dimensions leaderboards miss, from multi-repo coordination to failure recovery to cost per task, are the ones that decide whether an agent belongs in production. OpenHands gives you a direct way to test exactly that. You start locally in Agent Canvas, run agents against your own repositories with the model key you already use, and inspect every run before trusting the pattern with more. Once a workflow proves out, you can move it into OpenHands Cloud as a scheduled or event-triggered run, and the evaluation you ran by hand becomes an automation that runs without anyone kicking it off. The OpenHands team applies this same evaluation philosophy internally. Around 20% of commits to the OpenHands codebase are authored or co-authored by OpenHands agents, providing continuous feedback on real engineering workflows rather than benchmark tasks.

If you need governed evaluation at scale, you can go further. OpenHands Enterprise runs in your own virtual private cloud (VPC) with audit logs and cost attribution per workflow, so platform and security teams can trace what an agent changed and what it cost. Benchmarking an agent on your own work is the most reliable way to choose one, and the platform is built to make that test cheap to run and easy to repeat.

Start benchmarking AI coding agents on your own work

Public benchmarks are most useful as filters. They can flag whether a model is broadly capable, whether a scaffold is doing heavy lifting, and whether a leaderboard has gone stale, and that is enough to cut a long list of candidates down to a short one. The decision itself belongs to your own evaluation, measured on completion, reviewability, cost, setup friction, and governance.

A shortlist and the six steps above are enough to show you which agent fits your workload. Spin up your first evaluation run on OpenHands and score an agent against the work your team ships, whether you start with the open-source release, OpenHands Cloud, or a self-hosted enterprise deployment.

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Frequently asked questions about AI coding benchmarks

What is a good SWE-bench score?

Anything above 80% on SWE-bench Verified puts a model near the top of the pack, and as of July 2026 trackers put the newest models in the low-to-mid 90s. High scores mean less as the benchmark saturates, since crowded results stop separating models. SWE-bench Pro numbers run far lower on harder held-out tasks. You should read any single score against its scaffold and its date.

What is the difference between SWE-bench and HumanEval?

SWE-bench asks an agent to fix a real GitHub issue inside a repository until failing tests pass, while HumanEval asks a model to complete one isolated Python function. The first measures repository-level engineering with tools and context. The second measures raw generation, and current top models have saturated it, which is why SWE-bench variants carry more signal today.

Are AI coding benchmarks reliable?

They are reliable as directional signals rather than verdicts. Contamination, scaffold differences, and saturation can each inflate a published number. Your safest move is to treat every score as a claim about one setup at one point in time. Recent results with fully disclosed setups deserve the most weight.

Do benchmark scores predict how an AI coding agent performs on real work?

Scores transfer only partially to real work. A leaderboard number reflects a model plus a scaffold on curated tasks, while your repositories add environment friction, review standards, and cost limits no benchmark captures. Evaluating agents on your own tasks closes that gap, and OpenHands pricing covers the full range from local open-source runs to enterprise deployments.

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About OpenHands

OpenHands is the open-source platform for building and running AI coding agents, with the interface, automations, and control layer needed to go from a single local agent to a system running across an entire organization. The mission is to make agent-based software development accessible, transparent, and controllable by default. That starts in the open. The core framework is open source, giving developers and platform teams full visibility into how agents execute work and interact with their systems. The project has over 80,000 GitHub stars, over 9 million downloads, and contributions from hundreds of developers. OpenHands is used by engineers at large enterprises and fast-growing startups to build, run, and scale AI coding agents across real software engineering workflows. The long-term vision is to become the full stack AI coding agent platform for software engineering. Not just helping developers write code, but running meaningful parts of the software lifecycle.

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