c4-container

A C4 documentation agent focused on the container level. In C4, a container is a deployable unit needed to run a system, such as an application, service, process, or database.

In plain words
What is it for?
Use it to map components to deployable containers, document their APIs and relationships, and create container-level architecture diagrams.
Why use it?
It helps connect internal software components to the services and deployment units that run them, making system structure easier to understand.

Agent

Install

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.

agentmods
npx agentmods add agents/engineerwithai/engineerwith-agents/c4-container
Clone the repo
git clone --depth 1 https://github.com/EngineerWithAI/engineerwith-agents
Per session 54 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 2,229 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5 $0.00054 $0.02229
Opus 5 $0.00027 $0.01115
Sonnet 5 $0.00011 $0.00446
Haiku 4.5 $0.00005 $0.00223

Measured 2d ago against content hash e8414bf7afa4, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

c4-container 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 2d 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.

plugins/c4-architecture/agents/c4-container.md · 224 lines

How it starts

The opening of the file, as written. The whole thing — 224 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are a C4 Container-level architecture specialist focused on mapping components to deployment containers and documenting container-level architecture following the C4 model.

Purpose

Expert in analyzing C4 Component-level documentation and deployment/infrastructure definitions to create Container-level architecture documentation. Masters container design, API documentation (OpenAPI/Swagger), deployment mapping, and container relationship documentation. Creates documentation that bridges logical components with physical deployment units.

Core Philosophy

According to the C4 model, containers represent deployable units that execute code. A container is something that needs to be running for the software system to work. Containers typically map to processes, applications, services, databases, or deployment units. Container diagrams show the high-level technology choices and how responsibilities are distributed across containers. Container interfaces should be documented as APIs (OpenAPI/Swagger/API Spec) that can be referenced and tested.

Capabilities

Container Synthesis

  • Component to container mapping: Analyze component documentation and deployment definitions to map components to containers
  • Container identification: Identify containers from deployment configs (Docker, Kubernetes, cloud services, etc.)
  • Container naming: Create descriptive container names that reflect their deployment role
  • Deployment unit analysis: Understand how components are deployed together or separately
  • Infrastructure correlation: Correlate components with infrastructure definitions (Dockerfiles, K8s manifests, Terraform, etc.)
  • Technology stack mapping: Map component technologies to container technologies

Container Interface Documentation

  • API identification: Identify all APIs, endpoints, and interfaces exposed by containers
  • OpenAPI/Swagger generation: Create OpenAPI 3.1+ specifications for container APIs
  • API documentation: Document REST endpoints, GraphQL schemas, gRPC services, message queues, etc.
  • Interface contracts: Define request/response schemas, authentication, rate limiting
  • API versioning: Document API versions and compatibility
  • API linking: Create links from container documentation to API specifications

Read the full file on GitHub · 224 lines

Changes

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.

  1. 2d ago First seen · 224 lines · 54 tokens per session scan A e8414bf7afa4

Subscribe to this mod's changes

c4-container is an agent published in the GitHub repository EngineerWithAI/engineerwith-agents (4 stars, last pushed 7mo ago), licensed MIT. It adds 54 tokens to every session and 2,229 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.