Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add eric861129/SKILLS_All-in-one --skill fullstack-guardiangit clone --depth 1 https://github.com/eric861129/SKILLS_All-in-oneWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/eric861129/skills_all-in-one/fullstack-guardian)<a href="https://agentmods.dev/skills/eric861129/skills_all-in-one/fullstack-guardian"><img src="https://agentmods.dev/badge/skills/eric861129/skills_all-in-one/fullstack-guardian/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/eric861129/skills_all-in-one/fullstack-guardian"><img src="https://agentmods.dev/badge/skills/eric861129/skills_all-in-one/fullstack-guardian.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00164 | $0.01187 |
| Opus 5 | $0.00082 | $0.00593 |
| Sonnet 5 | $0.00033 | $0.00237 |
| Haiku 4.5 | $0.00016 | $0.00119 |
Grade A, and why
fullstack-guardian scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 6d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
This is a copy
89% identical to fullstack-guardian — 6 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 106 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Fullstack Guardian
Security-focused full-stack developer implementing features across the entire application stack.
Core Workflow
- Gather requirements - Understand feature scope and acceptance criteria
- Design solution - Consider all three perspectives (Frontend/Backend/Security)
- Write technical design - Document approach in
specs/{feature}_design.md - Security checkpoint - Run through
references/security-checklist.mdbefore writing any code; confirm auth, authz, validation, and output encoding are addressed - Implement - Build incrementally, testing each component as you go
- Hand off - Pass to Test Master for QA, DevOps for deployment
Reference Guide
Load detailed guidance based on context:
| Topic | Reference | Load When |
|---|---|---|
| Design Template | references/design-template.md |
Starting feature, three-perspective design |
| Security Checklist | references/security-checklist.md |
Every feature - auth, authz, validation |
| Error Handling | references/error-handling.md |
Implementing error flows |
| Common Patterns | references/common-patterns.md |
CRUD, forms, API flows |
| Backend Patterns | references/backend-patterns.md |
Microservices, queues, observability, Docker |
| Frontend Patterns | references/frontend-patterns.md |
Real-time, optimization, accessibility, testing |
| Integration Patterns | references/integration-patterns.md |
Type sharing, deployment, architecture decisions |
| API Design | references/api-design-standards.md |
REST/GraphQL APIs, versioning, CORS, validation |
| Architecture Decisions | references/architecture-decisions.md |
Tech selection, monolith vs microservices |
| Deliverables Checklist | references/deliverables-checklist.md |
Completing features, preparing handoff |
Constraints
MUST DO
- Address all three perspectives (Frontend, Backend, Security)
- Validate input on both client and server
- Use parameterized queries (prevent SQL injection)
- Sanitize output (prevent XSS)
- Implement proper error handling at every layer
- Log security-relevant events
- Write the implementation plan before coding
- Test each component as you build
What ships with it
10 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
- references/api-design-standards.md 7.6 KB
- references/architecture-decisions.md 12 KB
- references/backend-patterns.md 5.9 KB
- references/common-patterns.md 3.1 KB
- references/deliverables-checklist.md 8.6 KB
- references/design-template.md 2.1 KB
- references/error-handling.md 3.3 KB
- references/frontend-patterns.md 8.6 KB
- references/integration-patterns.md 8.1 KB
- references/security-checklist.md 2.5 KB
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 6d ago First seen · 106 lines · 164 tokens per session scan A 3000a75cdce9
fullstack-guardian is a skill published in the GitHub repository eric861129/SKILLS_All-in-one (52 stars, last pushed 4mo ago), licensed MIT. It adds 164 tokens to every session and 1,187 once invoked, about $0.0008 per session on Opus 5. A static security scan graded it A with 0 findings. It is 89% identical to fullstack-guardian, differing in 6 lines, and is treated as a copy.
Other skills, from other repositories
architect
This skill should be used when the user asks to "design system architecture", "evaluate microservices vs monolith", "create architecture diagrams", "analyze dependencies", "choose a database", "plan for scalability", "make technical decisions", or "review system design".
backend
This skill should be used when the user asks to "design REST APIs", "optimize database queries", "implement authentication", "build microservices", "review backend code", "set up GraphQL", "handle database migrations", or "load test APIs".
clerk-knowledge-patch
Use this guide when implementing, upgrading, or debugging Clerk authentication, authorization, Organizations, Billing, SDKs, components, or deployment architecture. Start with the migration notes, then open the matching reference.
anthropic-api-knowledge-patch
Use this skill when building or migrating integrations for the Messages API, hosted platform variants, Managed Agents, structured outputs, tools, streaming, prompt caching, model selection, or rate-limit handling. Treat the project's actual SDK types, API responses, and model metadata as authoritative when they differ…
apache-kafka-knowledge-patch
Use this skill when upgrading, configuring, extending, or operating Apache Kafka and its clients, Kafka Streams, Kafka Connect, MirrorMaker, KRaft, share groups, or tiered storage. Inspect the project's actual broker, client, metadata, and Java versions before applying version-dependent advice.
authjs-knowledge-patch
Use this patch to choose the maintained authentication path, avoid security-sensitive provider mistakes, and apply current Auth.js integration patterns. Read the topic reference before changing an affected flow; the quick reference prioritizes breaking behavior, security updates, and common implementation work.