---
title: "Builds: agents, coding tools, browser and interface"
type: community
source_tier: community
tags: [ideas, builds, agents, coding-agents, browser-use]
created: 2026-09-23
updated: 2026-09-23
confidence: medium
sources:
  - raw/x-repos/JoacoMarc__jev-harness-router.md
  - raw/x/bartlomein-2102060282369421714.md
  - raw/community/tjklug-com-posts-typesafe-jev-slopcheck.md
  - raw/x-repos/metalbear-co__jev-auto-approve.md
  - raw/x-repos/mizchi__jev-test-filter.md
  - raw/x-repos/Astro-Han__jev-harness.md
  - raw/x-repos/madeye__pi-jev.md
  - raw/community/reddit-com-r-llmdevs-comments-1wn3vc0-jev-coding-agents-what-i-learned-from-making.md
  - raw/community/reddit-com-r-sideproject-comments-1wmp3wn-jive-rethinking-the-agentic-loop-with-system-one.md
  - raw/community/reddit-com-r-ai-agents-comments-1wmtkds-i-built-a-browser-agent-where-every-step-is-a.md
  - raw/x/kylejeong-2100622054945095934.md
  - raw/x/AlanDaitch-2100757989212754085.md
  - raw/x-repos/RubyBrewsday__jevcumber.md
  - raw/community/callstack-com-blog-exploring-jev-for-mobile-qa-with-agent-device.md
  - raw/x/milindlabs-2100631847155994852.md
  - raw/x/VersunPan-2102201927178371280.md
  - raw/x/s16h_-2102434671326032148.md
  - raw/x-repos/zjunlp__JevLoop.md
  - raw/x-repos/abhishekashokvkumar__jev-mcp-dispatcher.md
  - raw/x-repos/chopratejas__invalidate.md
  - raw/community/reddit-com-r-llmdevs-comments-1wmzhn5-built-a-context-garbage-collector-for-llm-agents.md
  - raw/community/reddit-com-r-aiagents-comments-1wmq9ob-giving-ai-agents-their-own-email-inboxes-why.md
  - raw/x-repos/epiphany-dynamics__port-cleanup.md
  - raw/community/dev-to-gde-valid-schema-wrong-content-using-jev-to-guard-a-google-adk-agent-57o6.md
  - raw/community/dev-to-chorylee-i-ran-300-real-jev-calls-on-a-simulated-robot-fleet-the-bill-was-000737-45.md
  - raw/x-repos/baibizhe__jev-decision-benchmarks.md
  - raw/x-repos/rmalde__minecraft-agent.md
  - raw/x-repos/teknium1__hermes-and-jev-play-minecraft.md
  - raw/x-repos/valentynkit__jev-plays-pokemon-red.md
  - raw/x/umezawakanta13-2102008904842658002.md
  - raw/x-repos/valentynkit__jev-skip.md
  - raw/x/the_cyw-2101020586931875932.md
  - raw/x-repos/Tongyun1__Jev-in-the-Loop.md
  - raw/x-repos/vinilana__jev-eval-agent.md
  - raw/community/reddit-com-r-devops-comments-1wm4w4w-heyjev-shouldideploy-comment.md
jev_version: "jev-1.13.0"
summary: "Community builds putting Jev inside coding agents, harnesses, browser/device control, agent memory, games and UI: what Jev decides, reported numbers, pattern IDs, lessons for advising."
---

# Builds: agents, coding tools, browser and interface

> **TL;DR** 35 builds (sweep of 2026-09-23). Jev never runs the loop: it answers one bounded question per step (which tool, keep this chunk, is this test at risk, is this fact still true) while code owns options, thresholds and verification. Two careful A/B tests came out negative (jev-harness, JevLoop): read them before promising speed.

**How to read.** *Builder reports* = the builder's own numbers, one run on their own workload, unverified. API claims checked against [[reference/models-and-pricing]], [[concepts/state]], [[concepts/choice]]. OpenRouter/Vercel gateway routes are not in TypeSafe's docs ([[ideas/measurements]]). Pattern IDs: P01-P11, P35-P37 in [[ideas/patterns-agents]]; P12-P14, P34 in [[ideas/patterns-interface]]; P15-P18, P24-P27 in [[ideas/patterns-data]]; P22-P23 in [[ideas/patterns-business]].

## Coding agents and harnesses

| Build | Jev decides | Builder reports | P |
|---|---|---|---|
| [jev-harness-router](https://github.com/JoacoMarc/jev-harness-router) (Joaquin Marcoff) | Per turn, one call of ~20 questions: `score` difficulty and scope (code maps them to model tier and effort), `noul` per tool plus a ranking `choice`, skill `choice` gated by 4 `noul`s | 181 labelled turns: skill exact 90.0% vs 59.4% keyword baseline; tier too cheap 3.3% vs 19.9%; p50 351-376 ms; $0.169 per 1,000 turns (matches $0.042/Mtok, verified); one 20-question call 2.5x cheaper, 24x faster than 20 calls. Without the previous reply in `state` it lost to regex (exact tier 34.6% vs 69.3%) | P02, P08 |
| [Oko](https://x.com/bartlomein/status/2102060282369421714) (Bartlomiej Tyrpien) | MCP code search: BM25 keeps 30 chunks, one Jev call scores all 30 (~0.5 s), top 3 returned whole | 162 sessions: Claude Code 31% faster, Codex 18%, OpenCode 15%, 20-42% fewer agent tokens; speed came only after an AGENTS.md/CLAUDE.md rule on when to stop searching | P17 |
| [slopcheck](https://tjklug.com/posts/typesafe-jev-slopcheck/) (TJ Klug) | CI verdict on a diff: 18 patterns (16 `noul`, 2 `score`) on the whole diff, plus a `noul` per code-enumerated candidate line; hundreds of questions, one request | Fixture: 9,629 input tokens, 0.7 s; whole build $0.91 over 2,479 requests. Rewording one question: 0.06 → 0.84; `goal` first in state: 0.33 → 0.93; rerun drift ≤ 0.05. Compound checks split into two `noul`s joined in code | P10 |
| [jev-auto-approve](https://github.com/metalbear-co/jev-auto-approve) (MetalBear, runs on mirrord) | GitHub Action: 3 `noul`s (ready to merge, covered by tests, needs a human); approves only if each clears the threshold (default 0.9, mirrord 0.95) | No accuracy figures. Adds a "touches privileged automation" question; warns diff and discussion are untrusted input | P03, P06 |
| [jev-test-filter](https://github.com/mizchi/jev-test-filter) (mizchi) | 4-level `score` per test against the git diff; run at ≥ 2.0; low-confidence answers near the cutoff run anyway; any failure runs everything | 110 tests, 1 request: 3 selected, 23,423 input tokens, 1,296 ms, $0.00098 (price math verified). Reruns picked 8, then 7 | P17 |
| [jev-harness](https://github.com/Astro-Han/jev-harness) (AstroHan) | `noul` per ~2k-char chunk of each tool result ("needed for this step?"), keep at p > 0.5, raw kept for `read`; fails open | 30-task prototype 25/30 vs 22/30; TB4 follow-up (49 pairs) 2 vs 5 passes, +11.78% input tokens, +8.17% cost: **experiment closed**. Adding the agent's intent to `state` cut wrongly elided read-backs 33 → 12 | P07 |
| [pi-jev](https://github.com/madeye/pi-jev) (Max Lv) | Pi extension: word-overlap shortlist of 12 excerpts, Jev ranks direct evidence; optional skill `choice`, tool-output filter, 60 s cache, circuit breaker | Tool-output filter cut input tokens 55% but raised wall time against a fast hosted generator; thresholds untuned | P08, P07 |
| [sift-light](https://www.reddit.com/r/LLMDevs/comments/1wn3vc0/) (u/Deep_Bus_7488) | Optional judge over local code-search hits, batches of ≤ 8 and 64 KiB; `413` splits a batch | Returns partial status (`batchesFailed`, `candidatesUnjudged`), never a bare success/fail | P17 |
| [Jive](https://www.reddit.com/r/SideProject/comments/1wmp3wn/) (u/merijjeyn) | Terminal coding agent: tool calls replaced by DAGs of tool and Jev calls; LLM only for hard reasoning | Six self-chosen tasks: 1m41s-3m26s vs Codex 6m00s-29m33s, Claude Code 3m04s-32m02s | P01, P37 |

## Browser, mobile and computer use

| Build | Jev decides | Builder reports | P |
|---|---|---|---|
| [Hunch](https://www.reddit.com/r/AI_Agents/comments/1wmtkds/) (u/HAR5HA_7663) | Accessibility snapshot → operation and element, one request; hands off to the outer LLM on low confidence, a stalled page or a risky click; success checked in code | 153 ms median vs 678 ms gpt-4o-mini, both 24/24; 4-step form 3.4 s; same input moves p ~0.05. Typed values never reach Jev | P12, P06 |
| [Stagehand loop](https://x.com/kylejeong/status/2100622054945095934) (@kylejeong) | Accessibility tree as state, actions as options; Stagehand executes | $0.001 for one task on a remote browser | P12 |
| [Second-hand shopping](https://x.com/AlanDaitch/status/2100757989212754085) (@AlanDaitch) | Playwright + Jev per listing: discard, bid, or message the seller | ~26 listings/min, 406 ms per decision, USD 0.00085 for the search. It placed bids: money needs a P03 gate | P12, P17 |
| [jevcumber](https://github.com/RubyBrewsday/jevcumber) (Michael Poage) | Gherkin step → action kind, control, which quoted literal, submit or not, all picked from the live page | ~1 s per step; refuses below 0.6 (0.75 for page-sourced values); lockfile replays in CI with no API calls | P12 |
| [agent-device QA](https://www.callstack.com/blog/exploring-jev-for-mobile-qa-with-agent-device) (Mike Grabowski, Callstack) | Mobile accessibility snapshot → `choice` over press/fill/scroll/wait plus `pass`/`fail`/`incomplete`; text to type is baked into the option | 14 s run, $0.0023. `systemOne` + `choice()` matches [[reference/javascript-sdk]] (verified) | P14 |
| [Screenshot-free computer use](https://x.com/milindlabs/status/2100631847155994852) (@milindlabs) | On-device segmentation + OCR turn the screen into a text list; Jev picks what to click, in a loop | ~90 ms per decision | P14 |
| [WeChat group bot](https://x.com/VersunPan/status/2102201927178371280) (reviewed by @VersunPan) | Jev + DeepSeek over the Android accessibility tree, screenshot + local OCR fallback, last 10 messages | No numbers; warns WeChat can detect it and ban the account | P14 |
| [Jev-in-the-Loop](https://github.com/Tongyun1/Jev-in-the-Loop) (Tongyun1) | Codex plugin on jev-ultrafast: Codex plans and prepares the text to type; Jev picks action, target and input per step in local Chrome; stops at a handoff page (booking form) | Demos only, no numbers | P12 |

## Agent orchestration, memory and guards

| Build | Jev decides | Builder reports | P |
|---|---|---|---|
| [Metaview](https://x.com/s16h_/status/2102434671326032148) (@s16h_) | Production, every agent: split into small semantic questions with own thresholds; bugs fixed by adding a question | Sourcing searches minutes → seconds, "same accuracy, ~10x faster" | P01 |
| [JevLoop](https://github.com/zjunlp/JevLoop) (zjunlp) | 7 loop decisions (act?, tool, file, risk `score`, step ok, done, deliverable) compiled from a `DECISION.md`; LLM only writes | Hosted Jev ~390 ms per decision, 79% of wall clock. vs ReAct, 7 tasks: 5.9 s vs 3.4 s, 1 vs 3 LLM calls, 105 vs 360 output tokens, 6/7 vs 7/7 accepted. 78 ms of a 332 ms call is compute | P04, P03 |
| [jev-mcp-dispatcher](https://github.com/abhishekashokvkumar/jev-mcp-dispatcher) (abhishekashokvkumar) | NL → MCP tool `choice`; enum args `choice`; string args by a `noul` per word (value is always a literal substring); action count `choice` 1-5 | Proof of concept; no confidence gate, optional params not skipped (author's list). Compare [[cookbooks/function-calling]] | P13 |
| [invalidate](https://github.com/chopratejas/invalidate) (chopratejas) | 6 `noul`s per memory × event (bears on, still true, replaces, partial, hypothetical, directive); code applies the verdict; retiring a fact needs a second vote | 157 cases: 89.2% strict, 97.5% lenient, 0 false invalidations; $0.00006 per check; 20,000 memories vs one event: $0.110, 8.9 s | P09 |
| [jev-gc](https://www.reddit.com/r/LLMDevs/comments/1wmzhn5/) (u/Maleficent_College57) | Per OTel span: keep, compress to pointer, or archive; rules first, Jev only for ambiguous relevance | No numbers; false eviction unmeasured | P07 |
| [AgentMail](https://www.reddit.com/r/aiagents/comments/1wmq9ob/) (u/uriwa) | Every outbound agent email: genuine or abusive bulk; flagged sends rejected with `400` | Replaced a reply-karma scheme; "latency overhead is negligible" beside SMTP | P16, P03 |
| [Port Cleanup](https://github.com/epiphany-dynamics/port-cleanup) (Epiphany Dynamics) | macOS app: verdict per listening process (stop / keep / your decision) over a local evidence dossier | Kill advice needs ≥ 0.8; a human confirms every stop | P03, P06 |
| [ADK storyboard guard](https://dev.to/gde/valid-schema-wrong-content-using-jev-to-guard-a-google-adk-agent-57o6) (JimmyLiao) | `noul` on a Gemini ADK storyboard segment: does the text fit its duration? flag > 0.6 | 1 of 4 hand-written segments flagged (0.77). Reading time vs seconds is numeric ([[concepts/jaggedness-jev-1-13]]): fit poor | P16 |
| [Robot-fleet triage](https://dev.to/chorylee/i-ran-300-real-jev-calls-on-a-simulated-robot-fleet-the-bill-was-000737-45ai) (chorylee) | Per simulated incident: escalate `noul`, owning team `choice`, urgency `score` 0-2 | 300/300 calls; p50 0.53 s, p95 0.81 s; $0.00737 total; 91.3% agreement with template labels, not real faults | P22, P06 |
| [Tool-use benchmarks](https://github.com/baibizhe/jev-decision-benchmarks) (baibizhe) | Tool selection and call-or-abstain as `choice` (benchmark, not a build) | When2Call 74.84% accuracy but picked `tool_call` on 197 of 258 no-tool cases; BFCL relevance 87.50% (16 cases), irrelevance 86.74% | P13, P02 |
| [jev-eval-agent](https://github.com/vinilana/jev-eval-agent) (vinilana) | eve agent, 100 mocked tools: per step one `choice` over the tools + `respond_to_user` (101 ≤ 255 cap, verified); only the pick reaches the LLM; a `done` `noul` below 0.5 blocks the reply | Steps, cost and look-alike wrong tools vs the LLM seeing all 100, 6 tasks; results versioned in the repo, not captured | P13, P06 |
| [HeyJev shouldideploy](https://heyjev.ai/shouldideploy) ([u/geisbruch](https://www.reddit.com/r/devops/comments/1wm4w4w/weekly_self_promotion_thread/pb85iyt/), nullplatform team) | 18 typed questions on a described deploy (tests, rollback, availability); code turns probabilities into a verdict; questions editable | Public demo, not a gate: checks neither CI nor rollback. Suggested test: drop the rollback info, compare answers | P23 |

## Games and simulators

| Build | Jev decides | Builder reports | P |
|---|---|---|---|
| [minecraft-agent](https://github.com/rmalde/minecraft-agent) (rmalde) | LLM planner sets objective; Jev picks one action from harness-built options; Mineflayer executes | Ender Dragon from a fresh world in 8:43: 131 Jev decisions, 35 planner calls | P24 |
| [hermes-and-jev-play-minecraft](https://github.com/teknium1/hermes-and-jev-play-minecraft) (Teknium) | Same split, Hermes Agent plans | Reproduced in 7:45 for $0.963 ($0.010 Jev); controller median 211-227 ms; an LLM controller ~8x slower, ~20x the cost. Bad picks fixed by changing the options offered | P24 |
| [jev-plays-pokemon-red](https://github.com/valentynkit/jev-plays-pokemon-red) (valentynkit) | Code owns route and arithmetic; Jev only at branches | Median 621 ms (n=6, gateway shim), $0.14/hour; calibration withheld, sample too small | P24 |
| [Browser game timing](https://x.com/umezawakanta13/status/2102008904842658002) (@umezawakanta13) | Next action from game state | Jev HTTP 490.3 ms median inside 1,139.8 ms state-to-action (3 responses) | P24 |

## Interface elements

| Build | Jev decides | Builder reports | P |
|---|---|---|---|
| [jev-skip](https://github.com/valentynkit/jev-skip) (valentynkit) | Captions in 30 s segments, one `choice` each (`sponsor`, `intro`, `content` …) in one request; seek bar tinted by probability | 77% of crowd-marked sponsor seconds on 23 videos, 34 s false skips per hour, $0.0008 per video (gateway shim) | P34, P27 |
| [X timeline labeler](https://x.com/the_cyw/status/2101020586931875932) (@the_cyw) | Chrome extension labels each post clean, engagement bait, promo, secondhand or filler | $0.03 per 1,000 posts | P34, P16 |

## What these builds teach when advising

- **The options are the product.** Both Minecraft builds, jevcumber and agent-device fixed bad picks by changing what code offers (drop finished actions, bake the text into the option), not by rewording.
- **What goes in `state` decides accuracy.** The router lost to regex until it got the previous reply; jev-harness needed the agent's intent; slopcheck gained by putting `goal` first ([[guides/writing-instructions-and-criteria]]).
- **Hosted latency can eat the win.** JevLoop (79% of wall clock), jev-harness (closed) and pi-jev (slower) balance Oko and Jive. Batch questions per call, set a deadline with a fallback, measure ([[guides/testing-and-evaluation]]).
- **Keep "done" and irreversible acts in code.** Hunch verifies success itself; auto-approve, Port Cleanup and JevLoop gate risk with hard rules and a human; the bidding shopper needs one.
- **Fail toward safety.** test-filter runs everything on error, sift-light reports partial, invalidate needs two votes to retire a fact.
- **Test abstention.** Jev chose a tool on 197 of 258 no-tool cases; offer `none`/`other` ([[concepts/choice]]) or ask a separate `noul`.

## Related

- [[ideas/patterns]] — pattern index; [[ideas/consult]] — "could Jev help this project?"
- [[ideas/builds-apps]], [[ideas/tools-and-integrations]], [[ideas/head-to-head]], [[ideas/failure-reports]], [[ideas/patterns-emerging]] — sibling sweep pages
- [[ideas/repos-agents]] — earlier repo captures; [[concepts/how-to-build]] — official build guidance

## Sources

Links are inline in each row; the raw captures (2026-09-23) are listed in the frontmatter.