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MeshTen Lab

Our working thesis

v0.1, working draft, October 2026

Estimated tokens behind this research program

~14 billion tokens

~414 billion including cached context re-reads

Measured: ~1.7 billion new tokens (input plus output) and ~49.7 billion cached re-reads across Claude, Codex and Gemini in the 30 days to October 15, 2026. Estimate: that 30-day rate multiplied across the 242 days since February 15, 2026. Earlier months were likely lighter, so this is probably an upper-end estimate. Local model inference is not included.

Published by Sean Carr

Autonomous agents become reliable through the system around the model, not the model alone.

Models propose; plain code decides; a different model checks the work; and a claim counts only when the evidence came from outside the builder. This is our working design principle, not a guarantee that any model, reviewer, or gate is correct.

This is a living thesis about agentic workflows and autonomous software agents. It changes as studies land. Claims can be weakened or dropped when new evidence cuts against them. The articles below report observations; the claims connect those observations into ideas we can test.

We reviewed all 49 published Lab articles for this version. Most findings come from one organization's workloads, and many are tentative case studies. Several articles revisit the same incident or benchmark; links are not independent replications. Supporting evidence means the observation fits the claim, not that the full claim has been established.

Why the studies range so widely

The studies span memory, retrieval, security review, local inference, 3D assets and a game engine on purpose. We nested tests of the same claims inside fields that were unfamiliar to us, to see whether those claims held where we could not lean on prior expertise. If plain-code gates, cross-model checks and evidence from outside the builder only worked in familiar territory, that would weaken the thesis. These different settings let us ask whether a checker can miss the thing it claims to check, and whether an outside reference makes an output easier to judge. In the game engine study, a separate full walk of state exposed stale hashes that early tests missed. In the 3D asset study, agents built a coastal scene against a locked visual target, with independent scoring and no permission to change acceptance thresholds. Breadth is not independence; most studies come from one team's workloads.

H1 · Status: tentative

Self-report is not evidence

Our working claim is that independent, cross-model verification catches mistakes that a builder misses. A completion message is a lead to check against tests, artifacts, and observed actions. A different model can challenge the builder's assumptions, but its findings also need checking. The published cases support separating building from checking; they do not isolate the benefit of changing model family from the benefit of a fresh review.

Supporting articles

Evidence against / limits

Review severity is a judgment, not a measured production outcome. The cases are selected and sometimes overlap. A clean review of a supplied diff covers that scope only. We lack a controlled comparison of self-review, fresh review by the same family, and review by a different family with matched effort and independently established defects.

What would change our mind

On fresh tasks with known defects and equal review effort, self-review repeatedly catches as many real defects as independent review, with no increase in missed defects or false alarms. If a fresh reviewer helps but changing model family does not, we would drop the cross-model advantage from this claim.

How we will test this next

EXP-3: planned, pre-registered

The cases do not isolate a second model family from any fresh review pass. EXP-3 will use known-defect tasks with three equal-effort arms: self-review, a fresh same-family pass, and a different-family pass. A different-family gain of at least 10 percentage points over both other arms, with the planned statistical checks and few extra false findings, would upgrade H1; missing those conditions would weaken it. If the upper bound on its gain over a fresh same-family pass is below 10 points, we would drop the claimed family advantage.

Pre-registration recorded in commit 01fcdfdd. Study not yet run.

H2 · Status: contested

Plain code beats models at control decisions

We expect plain code to handle bounded routing, query planning, gating, recurring checks, and event recording better when the rule and input can be stated explicitly. A model can propose a plan or interpret an exception; code can apply the agreed rule and preserve what happened. The routing results support a narrow efficiency claim. They do not establish that general planning, unfamiliar retrieval, or policy judgment should become fixed rules.

Supporting articles

  • Zero-Token Planning: Removing All Planner Tokens With No Detected Accuracy Difference

    On reused questions, routing removed 152,239 planner tokens with no detected accuracy difference; this concerns query planning only.

    Article measurement
    deterministic routing eliminated 152,239 planner tokens to zero
  • Record What the Agent Did Before Asking a Model to Summarize It

    A raw event lookup took 0.2 seconds versus 16.6 for a model summary, but queries and outputs differed; no equivalent-answer speedup follows.

    Article measurement
    In the demonstration, a raw status query took 0.2 seconds. A summarized project query took 16.6 seconds and used one model call.
  • Preventing Code Slop and Enforcing Task Completion with Mechanical Gates

    Hook-only skip-told runs completed 56/58 and 29/29 items versus ungated 39/65 and 21/29; one repository and specific checks.

    Article measurement
    Hook-only runs completed 56/58 items on Claude (96.6%) and 29/29 on Gemini (100%). Ungated skip-told runs completed 39/65 and 21/29 items respectively.
  • The Hidden Infrastructure Tax in Multi-Agent Coding: An Estimated Replay of 39,526 Calls and an RTX 5090 Lab

    Hardened regex and a local two-stage cascade matched 100/100 on a 100-case synthetic PHI set (rules tuned in-sample) at 0.03 to 0.04 ms negative p50, and hybrid repo-filtered extraction reached 99.46% in-sample Micro F1 on 50 briefs. The CEO approved the local cascade on 2026-10-15 and it is now the default PHI admission check, with Claude Haiku as the fallback; an out-of-sample test is still planned.

    Article measurement
    Arm 4 Hybrid (Arm 0+ + repo-filtered qwen3:14b) matched 367/370 items (99.73% precision, 99.19% recall, Macro F1 99.40%, McNemar p = 2.65e-22 vs baseline Arm 0 at 59.98% F1 and p = 3.73e-09 vs Arm 0+ at 95.35% F1).

Evidence against / limits

A rule can encode the wrong policy, accept the wrong edit, read stale input, or never run. Faster recording does not verify authored handoff text or remote delivery. Script deployment has not been compared with a measured model baseline. The broad claim is contested because fixed retrieval rules failed badly on unfamiliar questions.

  • From Recurring AI Checks to Scripts: What Actually Ran?

    Tentative rollout: two jobs never ran and active alarms awaited delivery. No measured model baseline or input-freshness comparison establishes superiority.

    Article measurement
    Two of four selected jobs were reported never to have run; active checks produced clean results and pending notifications.
  • The AI Proposes, Plain Code Decides: Who Decides What the Rule Means?

    Four of 17 findings fit a retrospective policy grouping; one was intended behavior. Code still needs an agreed policy.

    Article measurement
    It does not describe four confirmed instances of a model escaping its intended authority.
  • A Code-Retrieval Index That Scored 0.94 In-Sample Scored 0.45 Out of Sample

    Compiled retrieval rules scored 0.45 out of sample versus 0.975 for agentic search. Fixed rules lost on unfamiliar retrieval.

    Article measurement
    Out of sample: E recall@5 0.45 and recall@10 0.45; hybrid F recall@5 0.45 on both runs vs the agent's 0.975 mean.
  • Preventing Code Slop and Enforcing Task Completion with Mechanical Gates

    Generic change checks were too weak: six incomplete runs passed. A gate does not establish that the right work happened.

    Article measurement
    Slop reduction and required items completed on skip-told briefs under mechanical gating.

    Article qualification: Six incomplete runs passed because generic file-change checks accepted the wrong edit.

  • Semantic Memory Living Paper: An Empirical Synthesis Across Session Memory Evaluations

    Rules written after seeing the questions caught six ambiguous cases but falsely flagged 19/158 correct answers (12%). This is in-sample control evidence, not a validated rule.

    Article measurement
    Rules written after inspecting the benchmark flagged all 6 ambiguous questions and falsely flagged 19/158 H-correct questions (12%). This was an in-sample result.
  • Our Determinism Hash Was Wrong on 74.3% of Steps

    The deterministic checker itself was wrong on 74.3% of steps. Code needs a genuinely separate reference check too.

    Article measurement
    Before fix: 22,290 of 30,000 steps had a wrong state hash (74.3%), the first at step 7,710.

What would change our mind

On independently written, unseen control tasks with identical inputs and permissions, a model planner repeatedly improves correct decisions enough to outweigh its measured delay and token use, while fixed rules miss required actions or need frequent manual exceptions. That would narrow which decisions we assign to code.

How we will test this next

EXP-4: planned, pre-registered

Fixed retrieval rules fell to 0.45 out of sample in the published code-retrieval study, so familiar-task results leave H2 contested. EXP-4 will compare a plain-code router with a learned fallback against a model router, scored only on unseen control tasks and counting manual exceptions needed. A code-router accuracy gain of at least 5 percentage points with an uncertainty interval above zero and at most 5 exceptions per 100 tasks would upgrade the bounded claim; missing those conditions would weaken it. A clear model-router gain of at least 5 points, or more than 10 code-router exceptions per 100 tasks, would lead us to drop the claimed advantage in this setting.

A Code-Retrieval Index That Scored 0.94 In-Sample Scored 0.45 Out of Sample

Pre-registration recorded in commit 01fcdfdd. Study not yet run.

H3 · Status: tentative

What the agent sees beats how it is asked

Our hypothesis is that context, memory, retrieval architecture, and mechanical gates move results more than prompt wording alone. Useful source spans and explicit checks can give an agent facts and feedback that instructions cannot supply. Yet prompts can have large effects, and extra context can mislead. Existing studies compare different interventions on different tasks, so the proposed ranking remains tentative until a direct comparison holds source access and effort constant.

Supporting articles

Evidence against / limits

There is no common experiment establishing that architecture generally matters more than prompting. Memory comparisons sometimes grant different source access; extra tokens and ingestion work belong in the result. A sampled score tie is not equivalence. Stale comments and confident hints can preserve the wrong answer, and a prompt checklist produced a large gain in its own study.

What would change our mind

In a pre-registered comparison on fresh tasks, with equal source access and total effort, prompt-only changes repeatedly match or exceed the accuracy and efficiency gains from retrieval, memory, and gates. Repeated losses from structured context would also weaken this claim.

How we will test this next

EXP-5: planned, pre-registered

Past studies compared different interventions on different tasks, leaving the proposed ranking tentative. EXP-5 will use identical fresh tasks, the same source access and total token budget, and vary only a prompt checklist versus retrieval architecture against a shared baseline. Retrieval beating the checklist by at least 10 percentage points with the planned statistical checks and no more than 10% extra tokens would upgrade H3; missing those conditions would weaken it. A clear checklist win of at least 10 points, or an upper bound below a 10-point retrieval gain, would lead us to drop the proposed large architecture advantage here.

Pre-registration recorded in commit 01fcdfdd. Study not yet run.

H4 · Status: tentative

The measuring setup is a leading source of error

We suspect harnesses, confinement, averages, and tuning on familiar questions are leading sources of error in agent evaluation. The setup can manufacture an apparent success, hide a failure, or blame a model for a broken tool. We therefore inspect intermediate artifacts, keep important failure categories separate, and test whether checkers can reject deliberately wrong behavior. Published examples establish that these errors occur; they do not yet rank them against all other causes.

Supporting articles

Evidence against / limits

The cases were chosen because something went wrong, so they cannot estimate the prevalence of measurement error. A confined run establishes its own boundary, not a numeric penalty relative to an unconfined run. Targeted checks still cover only their chosen cases. Correct measurements can support a narrow real improvement, and model reasoning failures remain after tool defects are fixed.

  • Zero-Token Planning: Removing All Planner Tokens With No Detected Accuracy Difference

    Among 40 classified errors, reasoning was the largest category (15), ahead of bad ground truth (9). This cuts against treating measurement as the dominant error source.

    Article measurement
    15 reasoning errors (37.5%), 10 retrieval misses (25.0%), 9 flawed ground-truth benchmarks (22.5%), 5 wrong-thread attributions (12.5%), and 1 judging variance (2.5%).
  • Five Optimizations That Measured Flat

    Five correct optimizations measured flat or near-flat. Checked code and plausible attribution did not establish a useful end-to-end gain; small samples limit tiny-effect claims.

    Article measurement
    Five correct optimizations that measured flat on whole-frame time
  • Reaching 120 FPS at Native 4K: The 3.5 ms That Wasn't Where We Looked

    Several plausible fixes measured neutral before the actual cost owner was isolated. Instrumentation narrowed the search but did not name the cause.

    Article measurement
    Candidate fixes in sequence: grid pre-filter neutral; static/dynamic partition neutral; flat cache 8%; supplied bounds zero; a static-prop premise falsified.
  • Asset Decode Was 83% of Boot. Parallelizing Textures Bought 5.6%.

    The first fix moved its phase only 5.6%; the after-fix boot comparison was inadmissible. A correct phase attribution did not establish the expected overall win.

    Article measurement
    First version (texture decode only, byte-identical): -5.6%. Model loaders: about 66% of the decode phase, not yet parallelized.
  • The Hidden Infrastructure Tax in Multi-Agent Coding: An Estimated Replay of 39,526 Calls and an RTX 5090 Lab

    Roughly 99% of the 121.82-hour summed concurrent call-time reduction came from software fixes and CPU worker sharding rather than the GPU, and the 100.0% PHI and 99.46% checklist rules were refined in-sample on the evaluation corpora.

    Article measurement
    roughly 99% of the time reduction comes from software and algorithmic fixes

    Article qualification: prospective out-of-sample holdout testing is required to establish unseen generalization.

What would change our mind

A prospective audit of a broad, randomly sampled set of agent studies finds that independently rebuilding harnesses, sealing access, using fresh questions, and reporting failure categories rarely changes conclusions, while model errors explain most discrepancies. We would then drop 'leading' and retain a narrower measurement warning.

How we will test this next

EXP-6: planned, pre-registered

The cases were selected because something went wrong, so they cannot tell us how often measurement errors matter. EXP-6 will take a prospective random sample of agent studies, independently rebuild each harness and seal access, then count how often conclusions change because of measurement defects versus model reasoning failures. With 40 complete audits, measurement changes in at least 30% and a clear excess over reasoning failures would upgrade H4; missing those conditions would weaken it. If the upper bound on measurement changes is below 20%, or reasoning failures clearly exceed them by at least 10 percentage points, we would drop 'leading' from the claim.

Pre-registration recorded in commit 01fcdfdd. Study not yet run.

Open questions

  • When does parallel orchestration improve completed work after accounting for memory, cleanup, and coordination? We keep this outside H1 to H4. One concurrency incident series and separate inference or pipeline profiles do not establish a general resource-allocation rule, so we do not add H5 in this version.
  • How much of independent review's value comes from a fresh context, a different model family, additional effort, or a better specification?
  • Can we compare prompt wording, source access, retrieval structure, and gates in one study with matched effort and fresh tasks?

Article mapping

Every article has a disposition. Open an article to inspect its method and limits. Not used means it does not directly test these claims.

View the complete evidence map

Changelog

v0.1, October 2026: Initial thesis with four testable claims, a complete article mapping, contrary and null results, and explicit conditions for changing our minds. No fifth claim added.

v0.1, October 15, 2026: Token estimate added, with measured usage, extrapolation method and limits. Added why the studies range so widely.

v0.1: planned upgrade studies EXP-3 to EXP-6 listed