TRUST 5 Quality Principles and Enforcement
This skill provides background knowledge on MoAI's quality model: the five
TRUST 5 principles, how agents enforce them, the 3-level harness, and the
language-aware toolchains that /moai gate runs. MoAI does NOT ship a
quality-validation library — quality is enforced through agents
(manager-develop, sync-auditor), slash commands (/moai gate,
/moai review), and the harness (minimal/standard/thorough).
Quick Reference
TRUST 5 Principles (Tested, Readable, Unified, Secured, Trackable) are quality dimensions, not code objects. Every code change is evaluated against all five.
Quality Mechanisms (the real enforcement layer):
/moai gate— runs lint + format + type-check + test in parallel as a pre-commit quality gate (<30s). Auto-detects the project language and runs the appropriate toolchain.manager-develop(run-phase) — implements viacycle_type∈ {tdd, ddd, autofix}; the chosen cycle shapes how tests and behavior are produced.sync-auditor— independent skeptical quality assessment with 4-dimension scoring (Functionality, Security, Craft, Consistency), scored as the harmonic mean of dimensions, not the average.- 3-level harness — minimal (fast validation), standard (default checks), thorough (full sync-auditor + TRUST 5). Auto-determined by the Complexity Estimator based on SPEC scope.
- LSP quality gates — phase-specific thresholds (run: zero errors/type-errors/ lint-errors; sync: zero errors, max 10 warnings, clean LSP).
The MoAI Quality Model
MoAI does not provide a Python SDK or any library for quality validation. Quality is enforced through the workflow, the agents, and the gate commands. This skill documents how those pieces fit together so a Claude invocation can reason about quality correctly.
How TRUST 5 is enforced per phase
| Phase | Quality check | Owner |
|---|---|---|
| plan | Capture LSP baseline; identify quality risks in the plan | manager-spec |
| run | Zero errors/type-errors/lint-errors; tests pass; coverage met | manager-develop (cycle_type shapes the approach) |
| sync | Lint clean (≤10 warnings); docs updated; TRUST 5 re-affirmed | manager-docs, then sync-auditor scores |
| audit | Independent 4-dimension scoring (Functionality/Security/Craft/Consistency) | sync-auditor |
cycle_type and quality (manager-develop)
The run-phase cycle_type selects how quality is built in:
- tdd — Test-Driven Development (RED-GREEN-REFACTOR). Behavior is specified by a failing test first, then implemented. Best for new features.
- ddd — Domain-Driven refactoring (ANALYZE-PRESERVE-IMPROVE). Behavior-preserving transformation of existing code. Best for refactoring and debt reduction.
- autofix — diagnostic-driven fixing (LSP / lint / type errors). Best for
/moai fixand regression recovery.
See Skill("moai-workflow-tdd"), Skill("moai-workflow-ddd"), and Skill("moai-workflow-loop") for the per-cycle mechanics.
TRUST 5 Principles
TRUST 5 is a mnemonic for five quality dimensions. Treat each as a question to ask of any change, not a score to compute.
- T — Tested: Does the change have tests? Are they green? Is coverage at or above the project threshold (85%+ by default)? For existing untested code, are characterization tests capturing current behavior?
- R — Readable: Is naming clear? Are comments in English (or the configured code-comments language)? Could a new contributor follow the logic without a walkthrough?
- U — Unified: Does the change match the file's existing conventions (naming, error handling, imports)? Is it formatted with the project's formatter? Consistency within a file beats personal preference.
- S — Secured: Are all external inputs validated? Does it follow OWASP guidance for web security? Are credentials kept out of version control (environment variables instead)? See moai-ref-owasp-checklist.
- T — Trackable: Does the commit follow Conventional Commits? Does it reference the SPEC / issue it implements? Can the change be traced back to a requirement?
For the per-principle assessment checklist and the "not applicable" guard, see TRUST 5 Principles.
Quality Gates and the 3-Level Harness
The harness level controls how deep quality validation goes. It is auto-determined by the Complexity Estimator based on SPEC scope.
| Level | What runs | When |
|---|---|---|
| minimal | Fast validation only (lint + type + test) | Small SPECs, low risk |
| standard | Default checks (lint + type + test + format) | Most SPECs |
| thorough | Full sync-auditor + 4-dimension TRUST 5 scoring | Large SPECs, high risk |
/moai gate is the lightweight pre-commit entry point: it runs lint +
format + type-check + test in parallel and applies no fixes. It is the
fastest way to get a quality signal. For deeper review use /moai review.
Language-Aware Toolchains
The quality gate auto-detects the project language and runs the appropriate toolchain. Tools that are not installed are skipped gracefully; projects with no recognized language marker pass the gate silently. This skill is language-neutral — the 16 supported languages are treated equally.
| Language | Lint | Format | Test |
|---|---|---|---|
| Go | go vet → golangci-lint | gofmt | go test |
| Python | ruff | black | pytest |
| TypeScript / JavaScript | eslint | prettier | jest / mocha |
| Rust | cargo clippy | rustfmt | cargo test |
| Java / Kotlin | (per project linter) | (per project) | junit |
| Ruby | rubocop | rubocop | rspec |
| PHP | phpstan / phpcs | php-cs-fixer | pest / phpunit |
| ... | (16 languages supported; auto-detected) |
For the full toolchain mapping and how /moai gate detects the language,
see Language-Aware Toolchains.
Module Reference
Each module is loaded on demand. Load the one relevant to the current task.
- TRUST 5 Principles — the five dimensions as assessment questions, per-principle checklists, and the "not applicable" guard.
- Proactive Analysis — how
/moai gate,/moai review, and/moai loopsurface quality issues proactively, and how to triage findings. - Best Practices — using WebSearch / WebFetch for up-to-date framework/library best practices, and validating against them.
- Integration Patterns — how quality fits into the SPEC workflow phases (plan/run/sync) and the harness levels.
Reference Files
- examples.md — worked TRUST 5 assessment examples and gate/review triage walkthroughs. Load when applying TRUST 5 to a concrete change.
- reference.md — the quality-mechanism reference: harness level detail, language toolchain table, agent roles, and the sync-auditor scoring model. Load when you need the authoritative mapping.
Works Well With
Agents (see .moai/config/sections/delegation.yaml for the 13-agent catalog):
manager-develop— run-phase implementation; owns the Tested and Unified principles through cycle_type.sync-auditor— independent 4-dimension quality scoring (Functionality / Security / Craft / Consistency).Explore(Anthropic built-in) — read-only codebase exploration before assessing quality.
Skills:
moai-foundation-core— TRUST 5 framework cross-reference and SPEC workflow foundations.moai-ref-testing-pyramid— test-pyramid strategy, coverage targets, and test patterns.moai-ref-owasp-checklist— OWASP Top 10 security checklist for the Secured principle.moai-workflow-tdd/moai-workflow-ddd/moai-workflow-loop— the cycle_type workflows that manager-develop uses.
Commands:
/moai gate— pre-commit quality gate (lint + format + type + test)./moai review— code review with security and MX-tag compliance./moai fix— auto-detect and fix LSP/lint/type errors./moai loop— iterative fix loop until resolved or max iterations.
Common Rationalizations
| Rationalization | Reality |
|---|---|
| "The linter warnings are false positives" | False positives should be suppressed with inline comments. Ignoring them trains the team to ignore real issues. |
| "Security scanning can wait until before release" | Security vulnerabilities compound. Late discovery means expensive rework. Scan continuously. |
| "Coverage is high enough, the remaining 15% is edge cases" | Edge cases are where production bugs live. The uncovered code is the riskiest code. |
| "Code review is subjective, automation is sufficient" | Automation catches syntax and patterns. Reviews catch design flaws, naming confusion, and missing abstractions. |
| "TRUST 5 is too bureaucratic for a hotfix" | Hotfixes without quality gates introduce the next hotfix. TRUST 5 on a hotfix is the minimum, not the maximum. |
Chesterton's Fence: Before removing a quality check, understand why it was added. Removing a gate without understanding its history repeats the failure it was designed to prevent.
Shift Left: The earlier a defect is found, the cheaper it is to fix. Quality checks belong in the development loop, not at the end of it.
Red Flags
- Linter or type-checker warnings suppressed globally instead of per-line
- OWASP checklist not consulted when handling user input or authentication
- Coverage report not generated for a commit that adds new functionality
- TRUST 5 dimension skipped with "not applicable" without justification
- Quality report generated but no action taken on identified issues
Verification
- Linter runs clean or remaining warnings have inline suppression comments with reasons (show the command output)
- OWASP checklist reviewed for security-relevant changes (show checklist references)
- Coverage report generated and threshold met (show tool output)
- All five TRUST 5 dimensions assessed (show assessment for each)
- Quality findings triaged with a resolution plan for each
- No global rule disabling in linter configuration
