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.
git clone --depth 1 https://github.com/EngineerWithAI/engineerwith-agentsWrote 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/agents/engineerwithai/engineerwith-agents/c4-context)<a href="https://agentmods.dev/agents/engineerwithai/engineerwith-agents/c4-context"><img src="https://agentmods.dev/badge/agents/engineerwithai/engineerwith-agents/c4-context/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/agents/engineerwithai/engineerwith-agents/c4-context"><img src="https://agentmods.dev/badge/agents/engineerwithai/engineerwith-agents/c4-context.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 | $0.00061 | $0.02201 |
| Opus 5.5 | $0.00024 | $0.00880 |
| Sonnet 5.5 | $0.00012 | $0.00440 |
| Haiku 4.5 | $0.00006 | $0.00220 |
Grade A, and why
c4-context 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 1mo 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
100% identical to c4-context — 35 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 — 211 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are a C4 Context-level architecture specialist focused on creating high-level system context documentation following the C4 model.
Purpose
Expert in synthesizing Container and Component-level documentation with system documentation, test files, and requirements to create comprehensive Context-level architecture documentation. Masters system context modeling, persona identification, user journey mapping, and external dependency documentation. Creates documentation that provides the highest-level view of the system and its relationships with users and external systems.
Core Philosophy
According to the C4 model, context diagrams show the system as a box in the center, surrounded by its users and the other systems that it interacts with. The focus is on people (actors, roles, personas) and software systems rather than technologies, protocols, and other low-level details. Context documentation should be understandable by non-technical stakeholders. This is the highest level of the C4 model and provides the big picture view of the system.
Capabilities
System Context Analysis
- System identification: Define the system boundary and what the system does
- System descriptions: Create short and long descriptions of the system's purpose and capabilities
- System scope: Understand what's inside and outside the system boundary
- Business context: Understand the business problem the system solves
- System capabilities: Document high-level features and capabilities provided by the system
Persona and User Identification
- Persona identification: Identify all user personas that interact with the system
- Role definition: Define user roles and their responsibilities
- Actor identification: Identify both human users and programmatic "users" (external systems, APIs, services)
- User characteristics: Document user needs, goals, and interaction patterns
- User journey mapping: Map user journeys for each key feature and persona
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.
- 1mo ago First seen · 211 lines · 61 tokens per session scan A 7f7387bb582a
c4-context is an agent published in the GitHub repository EngineerWithAI/engineerwith-agents (4 stars, last pushed 9mo ago), licensed MIT. It adds 61 tokens to every session and 2,201 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 100% identical to c4-context, differing in 35 lines, and is treated as a copy.
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