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The more general actualities of the day required no comment —
because facts can speak for themselves with overwhelming precision.

Joseph Conrad, Typhoon (1902) — himself a master mariner

Simple Man

Cut the chatter. Keep the work.

CI License: MIT Release Output tokens

You spend the day reading agents, not just running them — and most of what they write is not work: praise for your question, apologies, recaps of what just happened, suggestions nobody asked for, three paragraphs around one test.

Simple Man is the other voice at the helm — a captain who has run ships for decades and tells the crew exactly what they need: the blocker, the fix, the risk. Nothing else. The captain is the character; under the hood it is a measured policy of professional communication — short, factual, to the point — tested on 2,479 preregistered live calls — 266 of them real Claude Code sessions — raw records committed.

At Trafalgar, Nelson dictated England confides that every man will do his duty; his signal lieutenant swapped expects for confides — one hoist of flags instead of nine, the order untouched. That is the whole trade this skill makes, priced in tokens instead of flags.

What you get

  • Answers a third shorter. −32.4% output tokens across 84 real cases — measured, not advertised.
  • Zero lost facts. Every benchmark case ships a checklist of facts the reader acts on — blockers, failed checks, exact identifiers, risks. Simple Man keeps every required fact in exactly as many cases as answers written with no length pressure at all.
  • Findings that carry their fix. Location, consequence, one-line fix — nothing to follow up on.
  • It knows when not to compress. A requested format is a contract: exact counts, order and shape are checked before sending. Tutorials, teaching explanations and detailed reports are written in full — the shipped skill description triggered with zero false activations on them.

See it

Two panes streaming the same security review at the same rate: the no-policy answer runs to 1,215 tokens and keeps scrolling, Simple Man finishes at 276 tokens with the same two findings, locations and fixes.

Same model (claude-sonnet-5), same prompt. Left is what you read today:

No policy — 950 tokensSimple Man — 222 tokens

Findings

P1 — Panic on missing file in upload handler
Location: src/handlers/upload.rs:114

Issue: The code calls .unwrap() on Path::new(&filename).canonicalize(). canonicalize() returns an Err when the target file does not exist (or is otherwise inaccessible), and the unwrap() will panic in that case.

Impact: A missing file (e.g., client references a filename that was never uploaded, was deleted, or contains a path that doesn't resolve) crashes the request-handling thread. Depending on the async runtime/executor configuration, this can:

  • Terminate only the single request (best case, if caught by a panic boundary), or
  • Poison shared state / take down the worker if no panic isolation is in place.

Either way, it's an unhandled-error-as-crash pattern that should never be reachable from untrusted/external input.

Suggested fix: Replace .unwrap() with proper error propagation, e.g.:

let canonical = Path::new(&filename)
    .canonicalize()
    .map_err(|e| AppError::BadRequest(
        format!("invalid file path: {e}")
    ))?;

Return a 400/404 to the client instead of panicking. Add a test case covering a non-existent filename.

P2 — New PgPool created per request instead of reusing shared pool
Location: src/db/pool.rs:29

Issue: A new PgPool is instantiated on every request rather than reusing a single, shared pool constructed once at startup.

Impact: Each PgPool::new(...) (or equivalent) opens its own set of connections to Postgres. Under load this:

  • Rapidly exhausts available Postgres connections (hits max_connections on the DB server), causing connection errors for concurrent requests.
  • Adds significant per-request latency from repeated connection/handshake overhead.
  • Defeats the purpose of connection pooling entirely, since pools are not meant to be short-lived.

This is a correctness/scalability issue that will manifest as request failures and degraded throughput as concurrency increases, and could also affect other services sharing the same Postgres instance.

Suggested fix: Construct the PgPool once (e.g., in application startup / main.rs or a lazily-initialized static/OnceCell), then inject or pass a reference/clone (pools are typically Arc-backed and cheaply cloneable) into request handlers via app state (e.g., web::Data<PgPool> in Actix, State<PgPool> in Axum, etc.). Verify no other call sites have the same per-request instantiation pattern.

P1 — src/handlers/upload.rs:114: Path::new(&filename).canonicalize().unwrap() panics if the file doesn't exist, crashing the request thread. Fix: replace .unwrap() with proper error handling (e.g. .map_err(...)? returning a 4xx/5xx response) instead of panicking.

P2 — src/db/pool.rs:29: creates a new PgPool per request instead of reusing a shared pool, exhausting DB connections under load. Fix: construct the PgPool once at startup (e.g. in app state) and pass a reference/handle into each request instead of instantiating per-request.

Both findings, both locations, both fixes — nothing to follow up on. Every required fact kept on both sides.
No policy — 251 tokensSimple Man — 119 tokens

Subject: inventory-sync — Status Update

Hi [Manager],

Quick update on inventory-sync:

  • Kafka consumer rewrite is deployed to canary.
  • Performance: canary pods show p99 latency at 340ms, well within our 500ms SLO.
  • Issue: readiness probe on pod inventory-sync-7f9d8 is failing with connection refused on port 9090.
  • Rollout status: paused before proceeding to the remaining 90% of pods, pending investigation of the probe failure.

Will update once we've root-caused the connection issue and are ready to resume the rollout.

Thanks,
[Your name]

Status: inventory-sync

  • Kafka consumer rewrite deployed to canary.
  • Canary p99 latency: 340ms (within 500ms SLO).
  • Blocker: readiness probe failing on pod inventory-sync-7f9d8 — connection refused on port 9090.
  • Rollout to remaining 90% paused pending fix.
The blocker is labelled as one, and both facts that change what the manager does survive.
No policy — 840 tokensSimple Man — 338 tokens

Diagnosis

Root cause: A context deadline budget mismatch — the 200ms timeout attached to the context in CreateOrderHandler is smaller than the actual latency required by the downstream work performed inside pricing.Calculate.

Specifically:

  • CreateOrderHandler creates a context with a 200ms deadline (likely via context.WithTimeout(ctx, 200*time.Millisecond)) and passes that same context through the entire call chain: inventory.Reserve()pricing.Calculate().
  • inventory.Reserve() consumes ~40ms, leaving only ~160ms of budget remaining on that context by the time pricing.Calculate() is invoked.
  • pricing.Calculate() internally calls a currency conversion API that averages ~350ms.
  • Since the context's deadline is shared and cumulative across both calls (not reset or given its own independent timeout for the pricing step), the 200ms deadline is exceeded roughly 150–190ms into the currency conversion call.
  • The context's internal timer fires, cancels the context, and the HTTP client (or whatever transport pricing.Calculate uses to call the currency conversion API) returns context deadline exceeded because the request's ctx.Done() channel closed before the response arrived.

Exact point of failure: Inside pricing.Calculate(), specifically at the call site where it invokes the currency conversion API using the inherited context (e.g., the client.Do(req.WithContext(ctx)) or equivalent HTTP call). The deadline check that trips is the ctx.Err() / <-ctx.Done() evaluation performed by the HTTP client's transport layer during that outbound call, not any logic within pricing.Calculate itself.

Why inventory.Reserve() is unaffected: It completes in ~40ms, well under the 200ms budget, so it returns before the shared context's deadline is reached — the failure only manifests once the remaining budget (200ms − reserve time) is insufficient for the currency conversion API's ~350ms average latency.

Underlying issue in one sentence: A single 200ms context deadline is being shared across two sequential operations (inventory.Reserve + pricing.Calculate's external currency API call) whose combined/individual latency requirements exceed that budget, and there is no per-stage timeout or budget allocation to account for pricing.Calculate's dependency on a ~350ms external call.

Root cause: budget mismatch. CreateOrderHandler allocates a single 200ms timeout to the whole request context, but by the time inventory.Reserve() (~40ms) finishes, pricing.Calculate() has ~160ms left — less than the currency conversion API's ~350ms average latency. The timeout is too small for the slowest downstream call it must cover, so every call to the currency conversion API blows the deadline.

Exact failure location: inside pricing.Calculate(), at the call to the currency conversion API (the ctx.Done()/deadline check triggered during or after that HTTP call). inventory.Reserve() is not the problem — it completes well inside the budget.

Not yet diagnosed (would need code to confirm): whether pricing.Calculate derives a fresh sub-context/timeout for the currency API call or just inherits the parent's remaining deadline, and whether the 200ms figure was sized only for inventory.Reserve()'s SLA without accounting for pricing.Calculate()'s external dependency.

Same root cause, same exact failure location — and what is still unproven stays explicitly unproven.
Security review with fixes — 1,215 → 276 tokens
No policy — 1,215 tokensSimple Man — 276 tokens

Security Review Findings

Finding 1: Broken Object-Level Authorization (IDOR) — GET /api/orders/:orderId
Location: routes/orders.js:52
Class: CWE-639 (Authorization Bypass Through User-Controlled Key) / OWASP API1:2023 – Broken Object Level Authorization

Description: The endpoint authenticates the request (valid session required) but does not authorize it — it never verifies that the fetched order.userId matches req.session.userId. Any authenticated user can enumerate or guess orderId values (sequential IDs, UUIDs leaked elsewhere, etc.) and retrieve other users' order data.

Impact:

  • Horizontal privilege escalation: disclosure of other customers' order contents, shipping addresses, pricing, and any PII embedded in the order record.
  • If order IDs are sequential/predictable, mass scraping of all orders in the system is trivial.

Severity: High

Finding 2: Broken Object-Level Authorization (IDOR) — PATCH /api/orders/:orderId/status
Location: routes/orders.js:80
Class: CWE-639 / OWASP API1:2023 – Broken Object Level Authorization

Description: Same missing ownership check as Finding 1, but on a state-mutating endpoint. Any authenticated user can modify the status field of any other user's order by supplying its orderId.

Impact:

  • Unauthorized write access: an attacker can cancel, mark-shipped, mark-delivered, or otherwise tamper with other users' orders.
  • Business-logic abuse (e.g., prematurely marking orders "delivered" to trigger downstream automation, fraud, or dispute leverage).

Severity: High

Finding 3: Missing Input Validation on statusPATCH /api/orders/:orderId/status
Location: routes/orders.js:80
Class: CWE-20 (Improper Input Validation) / lack of allow-list enforcement for state transitions

Description: The handler writes the incoming request value directly into order.status without validating it against an allow-list of legal states (e.g., pending, paid, shipped, cancelled, delivered) or enforcing valid state-transition rules.

Impact:

  • Data integrity corruption: arbitrary/malformed strings can be persisted as order status, breaking downstream logic (fulfillment, reporting, notifications) that assumes a fixed enum.
  • Illegal state transitions (e.g., jumping from pending directly to delivered, or reverting a cancelled order) may bypass business rules and any invariants other code paths depend on.
  • Depending on how status is later used (rendered in UI/emails, used in DB queries, passed to downstream services), an unvalidated string could contribute to secondary issues (stored XSS if reflected unescaped, log injection, etc.) — worth checking consumers of this field.

Severity: Medium (compounds with Finding 2 into High when combined — unauthorized and unvalidated writes)

Summary / Remediation Guidance (not exhaustive, findings-only requested but noting root cause) Both endpoints need an ownership check (order.userId === req.session.userId, returning 403/404) before returning or mutating the resource. The PATCH endpoint additionally needs status validated against a fixed enum/allow-list and, ideally, a state-transition guard rather than an unconstrained overwrite.

routes/orders.js:52 — GET /api/orders/:orderId

  • IDOR: authenticated user can read any order by ID (no order.userId === req.session.userId check).
  • Fix: after fetch, if order.userId !== req.session.userId, return 403/404.

routes/orders.js:80 — PATCH /api/orders/:orderId/status

  • IDOR: same missing ownership check — any authenticated user can modify any other user's order status.
  • Fix: same ownership check before update.
  • Unvalidated input: status accepted as arbitrary string, written directly to order.status — allows invalid/unexpected state values (data integrity risk, possible logic bypass if downstream code branches on status).
  • Fix: whitelist allowed status values (enum check) before update; reject with 400 otherwise.
Dockerfile + run commands — 2,045 → 443 tokens

No policy — 2,045 tokens

Here's a complete, production-ready Dockerfile plus the commands to build and run it.

Dockerfile

# syntax=docker/dockerfile:1
FROM node:20-alpine

WORKDIR /usr/src/app

# Copy only manifest files first for better layer caching
COPY package*.json ./

# Install exact, reproducible deps (requires package-lock.json in context)
RUN npm ci --omit=dev && npm cache clean --force

# Copy application source
COPY . .

# node:20-alpine ships with a built-in non-root 'node' user (uid/gid 1000)
# Give it ownership of the app directory, then switch to it
RUN chown -R node:node /usr/src/app
USER node

ENV NODE_ENV=production
ENV PORT=4000

EXPOSE 4000

# DATABASE_URL and JWT_SECRET are intentionally NOT set here —
# they must be injected at runtime via `docker run -e` / secrets manager

# Adjust to your actual entry point (e.g. dist/main.js, index.js)
CMD ["node", "server.js"]

Build command

docker build -t node-api:latest .

Run command

docker run -d \
  --name node-api \
  -p 4000:4000 \
  -e DATABASE_URL="postgresql://user:password@host:5432/dbname" \
  -e JWT_SECRET="replace-with-a-strong-secret" \
  --restart unless-stopped \
  node-api:latest

Notes / caveats

  • Entry point: CMD ["node", "server.js"] assumes your start file is server.js. Change it to match your actual entry (e.g. dist/index.js if you build TypeScript first — in that case add a RUN npm run build step before switching to the non-root user, and copy source before npm ci accordingly).
  • package-lock.json required: npm ci fails without a lockfile in the build context. Make sure package-lock.json is committed and not excluded by .dockerignore.
  • .dockerignore: add one with at least node_modules, .git, .env, npm-debug.log to keep the build context small and avoid leaking local secrets into the image.
  • Never bake secrets into the image: DATABASE_URL/JWT_SECRET are supplied only at docker run time (or via --env-file, Docker secrets, or your orchestrator's secret store) — they are not ENV instructions in the Dockerfile, so they won't be persisted in image layers.
  • Env file alternative: instead of -e flags, you can use --env-file .env.production if you keep a local (gitignored) env file with DATABASE_URL=... and JWT_SECRET=....
  • Permissions: chown -R node:node walks the whole app directory at build time; fine for typical API codebases, but if your image is very large consider a multi-stage build to keep the final image lean.

Simple Man — 443 tokens

FROM node:20-alpine

WORKDIR /app

COPY package*.json ./
RUN npm ci --omit=dev

COPY . .

RUN addgroup -S appgroup && adduser -S appuser -G appgroup \
    && chown -R appuser:appgroup /app

USER appuser

EXPOSE 4000

CMD ["node", "index.js"]

Run:

docker build -t node-api .

docker run -d \
  -p 4000:4000 \
  -e DATABASE_URL="postgres://user:pass@host:5432/db" \
  -e JWT_SECRET="your-secret" \
  --name node-api \
  node-api

Notes:

  • CMD ["node", "index.js"] — replace index.js with your actual entrypoint (e.g. dist/main.js if compiled, or npm start if you prefer that instead of a direct node call).
  • npm ci --omit=dev skips devDependencies; drop --omit=dev if the app needs a build step post-copy.
  • alpine lacks bash/many glibc-dependent native modules; if any dependency needs native compilation, add RUN apk add --no-cache python3 make g++ before npm ci.

All pairs above are real captured answers from the committed benchmark run — nothing is hand-written for this README. Raw records: evals/releases/v0.3.1/.

Install

Claude Code — global, for every project:

npx skills add Maksim-Burtsev/simple-man -g -a claude-code -s simple-man -y

Project-level only — drop the -g. Invoke it explicitly with $simple-man, or let the agent activate it from the request.

Portable Agent Skill

The same skill installs into any supported agent by changing -a:

npx skills add Maksim-Burtsev/simple-man -g -a codex -s simple-man -y

Always-on Codex policy

The policy on every turn, without invoking the skill. The installer writes ${CODEX_HOME:-$HOME/.codex}/AGENTS.md and installs the skill; rerunning it updates that block in place:

curl -fsSL https://raw.githubusercontent.com/Maksim-Burtsev/simple-man/v0.3.2/install.sh | bash

For always-on Claude Code, copy AGENTS.md.snippet into your global ~/.claude/CLAUDE.md.

Codex plugin and other agents

Codex Plugin

codex plugin marketplace add Maksim-Burtsev/simple-man --ref v0.3.2
codex plugin add simple-man@simple-man

Installing the skill or the plugin makes Simple Man available; it does not enable the always-on policy — only the installer or a copied snippet does that. See INSTALL.md for other agents and project-level setup.

Benchmark: Simple Man vs no policy

Median answer length: 833 tokens without a policy vs 520 with Simple Man (−32.4%). Cases keeping every required fact: 66.7% in both arms.

−32.4% output 0 facts lost 0% in sessions
Median answer drops from 833 to 520 tokens (95% CI [−23.2%, −43.8%]) Keeps every required fact in 66.7% of cases — identical to the no-policy baseline 81 real Claude Code sessions on SkillsBench: cost +2.8% median, CI [−7.2%, +10.7%], p = 0.71 — no saving, and the README says so

This is not a vibe check — every step of the pipeline is built so the numbers cannot be massaged:

How the benchmark works: preregistered gates and corpus, hidden validators and a blind holdout wave, five arms on the same model and prompt, blind pairwise judging in both orderings, every number rebuilt from raw records in CI, and failures published rather than hidden.

Four preregistered live runs on claude-sonnet-5, 2,479 calls, all raw records committed under evals/releases/ — preregistered by commit (v0.3.1, session-v1), rebuilt by make bench-v3-check and make session-check.

Full comparison table, controls, methodology, and what did not ship

Latest run: 84 output cases across 12 categories (38% Russian), 40 activation cases, 3 real agentic coding fixtures with hidden validators, blind pairwise judging with position swap, and a holdout wave written by authors who never saw earlier results.

The shipped policy against its predecessor and controls:

previous v0.2 policy shipped policy one sentence of "be concise" no policy
Required facts kept 57.1% 66.7% 67.9% 66.7%
Blind preference vs shipped 8 wins 48 wins, 28 ties
False success claims 0
Requested format kept 82.1% 81.0% 82.1% 76.2%
Coding fixtures passed 2/3 2/3 2/3 2/3

The previous policy compressed hardest (−66% output) by dropping required facts — that is why it was replaced. The shipped policy restores fact retention to the no-policy level while still removing a third of output length.

On cost, honestly. Output-token percentages are not session savings, so we measured sessions: 266 real Claude Code runs on SkillsBench through Harbor — the protocol JetBrains used for caveman and benjamin-plus — same model, low effort, each task verified by its own tests.

81 paired sessions, policy vs none median paired delta 95% CI p
cost +2.8% [−7.2%, +10.7%] 0.71
total tokens +2.1% [−6.4%, +15.8%] 0.71
turns 0.0% [−5.9%, +10.0%] 0.99
task reward 8 better / 14 worse / 59 tie sign 0.29

Nothing moves. In a tool-using session the visible answer is about one percent of the tokens, and the policy does not touch the other ninety-nine. If you install Simple Man to cut your bill, you will not: the one sentence "be concise" is in fact cheaper in sessions than the policy (+13.1% cost for the policy against it, p = 0.036) at the same task reward. What the policy buys is a shorter, fact-complete answer for the person reading it — nothing else, and the reward column above leans the wrong way (not significant; the run notes show where it went).

What a sentence does not give you is a specification: findings that must carry their location, consequence and one-line fix; refusals that must name the target, the missing precondition and the safe procedure; failed checks that must report the exact failure; requested shapes treated as contracts; and a description that routes away from tutorials and detailed reports. That is the part you can read, and hold the policy to, in AGENTS.md.snippet. Whether that specification beats a sentence category by category was tested on 60 new cases concentrated in destructive_risk, security and status: facts kept are level (71.7% vs 73.3% for the sentence), status is the policy's best category (100%), and the blind judge prefers the sentence 23–15 and even no policy 23–11 — because it rewards the volunteered alternative or extra verification step that the policy tells the agent to leave out. That is the trade you make, stated in the open rather than in the flattering cells.

What did not ship, published rather than hidden: the first candidate failed its gates outright; the second beat the shipped policy decisively but only tied the one-sentence control, and its promotion is an explicit owner decision over the automated gate result, recorded with the trade-offs in DECISION.md. The session run found no savings and a reward lean against the policy; the category scout found the judge prefers longer answers. Gate tables, a mis-specified gate we scored as failed rather than quietly fixed, and every run's full analysis live in evals/releases/.

Older Codex-based suites and what runs offline are described in evals/README.md.

What it changes — and what it never touches

Changes: no preamble, praise, recap or filler; answer first; every review or security finding carries its location, consequence and one-line fix; refusing a destructive action names the target, the missing precondition and the safe procedure; a failed check reports the exact failure and where to look next; qualifiers survive — "no known remaining risks" is never shortened to "no remaining risks".

Never touches: repository search, usage search, dependency tracing, impact analysis, validation, test/lint/typecheck effort, proactive detection of related correctness issues.

Agent support

The full skill (skills/simple-man/SKILL.md) and a compact always-on policy (AGENTS.md, generated from AGENTS.md.snippet by scripts/sync_surfaces.py) cover Claude Code, Codex, Gemini CLI, Cursor and any AGENTS.md-compatible agent.

Per-agent paths
Agent/tool Path
Claude Code skills/simple-man/SKILL.md, or CLAUDE.md for always-on
OpenAI Codex / Agent Skills skills/simple-man/SKILL.md, AGENTS.md, AGENTS.md.snippet
Gemini CLI GEMINI.md, or configure Gemini to read AGENTS.md
Qwen Code AGENTS.md, optional global skill copy
Cursor / Windsurf / Cline / Copilot / Continue / Zed / Junie AGENTS.md, or copy AGENTS.md.snippet into that agent's native rule file
Amp / OpenCode / Kilo / Roo / Aider / other AGENTS.md agents AGENTS.md

Always-on project files do not invoke $simple-man; they inline the compact runtime policy to avoid loading full skill overhead on every turn. Agent-specific dotdir rule files are not committed here — they are target-project activation files, not the source of the skill.

License

MIT — see LICENSE.

Releases

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