harness-self-improvement CAP-0023 · active

Improving its own scaffolding from failures

Whether an agent system can read its own failure traces and rewrite the prompts, tools and policies it runs inside so later runs do better, with no person making the edit.

Also called: self-improving agents, harness optimization, scaffold evolution, prompt optimization

Tags: agentic, autonomous-agent, coding-agent

Filed 2026-09-14 when the DAIR harness-engineering collection arrived and the term matcher could route none of its "let the harness learn" papers (DSPy, GEPA, Darwin Gödel Machine, Meta-Harness, Continual Harness, Prime Agent): the map had no leaf for the competence this catalog's own ambition rests on. Fixing its own mistakes covers correcting an output; this covers correcting the system that produced it. The catalog's rule for evidence here is the one Hashimoto's ratchet and the Self-Harness paper set: a held-out split the promotion decision never reads, and a matched-compute baseline.

What counts as this capability

Scope boundary used when deciding whether a paper is really about this capability, rather than merely mentioning it.

In scope when the paper's subject is a system editing its own prompts, tools, memory, or control code from traces or scores, with a measured before-and-after on tasks. NOT in scope for fine-tuning weights (that is training), for a model fixing one output (self repair), or for a person hand-editing a harness and measuring the effect (that is harness engineering, filed under the technique used).

Claims

Techniques

  • Attribute recurring failures before editing the harnessprocess
    Aggregate failing trajectories across tasks into recurring failure groups, then run a fixed number of analyst-critic-engineer refinement passes plus a moderator to produce one modification specification, which a coding agent implements and
  • Compute lifecycle consequences in the harness, not in the motooling
    Where component dependencies and cleanup effects are explicitly represented, have the runtime enumerate legal teardown continuations and compute or verify the resulting state, leaving the model only the higher-level goal choice.
  • Consolidate only experience that survives state revisiontraining
    Alternates fast edits to an explicit textual state (validation-gated) with distillation into the policy, keeping only trajectories that the updated state makes newly or persistently better than state-free execution, weighted by per-token di
  • Contrastive, module-scoped harness evolution on benchmark-diprocess
    Collect success and failure trajectories for the same task, aggregate the contrast across tasks into recurring behavioural deficiencies, attribute each to one of five harness modules, evolve each module inside its own modification scope, th
  • Critic-gated refinement stages with a simulated rebuttalprocess
    Run every stage of an autonomous research loop as candidate, critic, refine with a bounded number of rounds, where the critic can accept, request refinement or reject, and close the loop with a simulated peer-review and rebuttal before the
  • Distill lessons from past attempts into memoryprocess
    After each task, have the agent judge whether it succeeded, distill a short reusable strategy or warning from the attempt, store it, and retrieve only the relevant ones at the start of later tasks.
  • Evolve a decision knowledge base from solver failures, gatedprocess
    Accumulated solver and trajectory-validation failures are summarized into candidate add/modify/delete/merge edits to an initially empty knowledge base of scene-conditioned allowed and forbidden maneuvers, and an edit is kept only if re-runn
  • Evolve the data-generation pipeline on pilot sets before scaprocess
    A controller compiles a data-preparation runtime specification, generates a small pilot dataset, assesses it against domain-selected quality criteria, and emits an adapter that revises specific pipeline components while preserving their int
  • Find the responsible agent by hint injection, then learn froprocess
    For each failed run, inject a ground-truth-derived hint into one agent at a time in reverse execution order until the failure resolves, then contrast that agent's original and hint-corrected outputs to write its prompt update, clustering si
  • Gate harness edits on both source cases and a resampled heldprocess
    Each mined edit to the harness's knowledge or tool library is applied in a sandbox and promoted only if it strictly improves accuracy or cost on the trajectories it was mined from and does not regress on a stratified held-out case set resam
  • Gate skills on sampled coalition knockouts, then mask after process
    At acceptance time, score a candidate bank by the averaged value loss from knocking out randomly sampled skill subsets rather than by aggregate reward alone; at deployment, greedily drop transferred skills whose removal improves retrieval s
  • Gated, attributed, typed edits to an agent-queried ontologyprocess
    Keep the semantic layer outside the prompt as queryable MCP tools; when the agent fails, diagnose from traces, attribute the failure to the schema, content or tool level, write a typed edit at that level, and keep it only if a paired evalua
  • Generate prompt edits only from failures, gate on a preservaprocess
    Sample textual gradients only from examples the current prompt answers wrongly, generate several candidate prompts, and keep one only if its improvement on the hard batch beats a scheduled penalty times its regression on a held-back sample
  • Learn skills per stage from the supervision that stage offerprocess
    Distil reusable text skills for hypothesis generation from a multi-dimensional discriminator's critique of the whole generated hypothesis set, and skills for experiment design and execution from testing trajectories scored against ground-tr
  • Let the agent revise its own harness, regression-gatedprocess
    Cluster failed traces into signatures, have the same fixed model propose a few minimal harness edits, and promote only edits that improve one split without degrading another.
  • Mine tiered lessons from own trajectories, principles firstprocess
    After each labelled run, an agent distills successes into 'golden' lessons and failures into 'warning' lessons, consolidates them by embedding similarity into a three-tier library (principles, patterns, cases), and retrieves from it top-dow
  • Promote a fix only against targeted, protected and negative-process
    For each recurring failure, write a patch with an explicit scope and injection point, then admit it only if it fixes its targeted cases, leaves a protected regression suite unharmed, and does not fire on negative controls; refuse or defer c
  • Recursively search the video context-construction programprocess
    An LLM proposer repeatedly rewrites the executable program that selects, retrieves and packs video evidence into a frozen VLM's bounded context, keeping only candidates that strictly improve development accuracy.
  • Reward-gated skill distillation from the agent's own failed process
    The orchestrator answers blind, is shown the gold, classifies the gap as operational/unreachable/already-correct, writes a candidate skill only for operational gaps, and the skill is retained in an external library only if it lifts the vali
  • Rewrite the agent's tool-use policy prompt from realized outprocess
    A separate Policy Agent reads a batch of decision traces paired with realized portfolio returns and rewrites the trading agent's whole system prompt — tool selection, query formulation, verification and sizing rules — before the next batch
  • Separate self-judged scores from verifier rewards and measurprocess
    Withhold verifier-computed rewards from the agent during exploration while logging them benchmark-side, so the agent's own step scores can be compared against ground truth and against later held-out improvement.
  • Store jailbreak failures as wrapper-level rules in persistenprocess
    On a detected unsafe response, an LLM distills the attack's structural wrapper into a labelled rule in an external memory, and later inputs are classified into a wrapper label that selectively triggers at most two matching rules before gene
  • Target guidelines at flip-prone steps found by resamplingprocess
    An offline analyzer re-issues each recorded prompt N times and scores response agreement per step; steps below a consistency threshold are turned by an LLM into short guidelines stored in episodic memory and retrieved into future runs of si
  • Verify harness edits on behavior-matched tasks with an attriprocess
    For each proposed harness modification, select verification tasks linked to the supporting trajectories plus regression-risk tasks, run both old and new harness on them, and accept only if the trajectory evidence attributes the improvement

Sources

Every paper, post or observation behind this capability. Ones cited by a claim show the claim and its stance; ones filed directly are about the capability but have no claim drafted from them yet. Open one to add support or contest it.

Suggest a change

Capabilities are a way of carving up the subject, and carvings are arguable. Say so if this one is wrong — especially a proposed one, which a pipeline added because several papers used the same framing, not because anyone decided it was right.