Agent App vs Skills and Knowledge

Agent Skills, Agent Knowledge, and Agent App answer different questions.

Standard	Answers	Entry
Agent Skills	How does the agent do the work?	SKILL.md
Agent Knowledge	What trusted facts and context can enter the model?	KNOWLEDGE.md
Agent App	Which UI, workflows, storage, services, entries, capability dependencies, tools, artifacts, and evals make up an installable app?	APP.md + runtime package

Decision tree

flowchart TD
  Asset[Candidate asset] --> DoQ{Does it tell the agent how to act?}
  DoQ -->|Yes| Skill[Agent Skill]
  DoQ -->|No| FactQ{Does it provide facts, sources, policy, examples, or context?}
  FactQ -->|Yes| Knowledge[Agent Knowledge]
  FactQ -->|No| ComposeQ{Does it compose entries, dependencies, permissions, and deliverables?}
  ComposeQ -->|Yes| App[Agent App]
  ComposeQ -->|No| Other[Host project file]

How they work together

flowchart LR
  User[User launches app entry] --> App[APP.md entry]
  App --> Skill[Agent Skill: how to do it]
  App --> KSlot[Knowledge Template: required knowledge slot]
  KSlot --> KPack[Agent Knowledge Pack: concrete customer facts]
  App --> Tool[Agent Tool: callable capability]
  App --> Artifact[Agent Artifact: deliverable]
  App --> Eval[Eval / QC: deliverability]

Agent App does not copy procedural details from Skills or factual content from Knowledge. It declares how those assets are composed, and may carry its own UI, workers, storage schemas, and business workflows. Runtime still happens under host authorization through the Capability SDK.

Content engineering example

Asset	Correct place	Reason
How to interview a founder and compile IP facts	Agent Skill	It is a knowledge-production method.
Founder history, voice, boundaries, quotes	Agent Knowledge	It is source-grounded persona data.
How to draft articles and remove AI tone	Agent Skill	It is writing and review procedure.
Project home, knowledge pages, content factory, /IP Article, /Review Report	Agent App	They are app UI and user-visible entries.
Competitor research, image generation, Feishu export	Agent Tool	They are external capabilities.
Article draft, script batch, strategy report	Agent Artifact	They are durable deliverables.
Fact grounding, voice fit, publish readiness	Eval / Agent QC / Evidence	They are quality and trust checks.

Common mistakes

• Embedding customer data in an official app package.
• Putting full writing procedures in APP.md instead of a Skill.
• Treating Knowledge as executable instructions.
• Inventing a new tool protocol for one app.
• Letting a cloud registry become a hidden Agent Runtime.
• Hardcoding business entries in host core instead of generating them from app projection.

Fixed conclusions

• App is a complete application package; execution happens in the host runtime and capability calls must go through the Capability SDK.
• Skill is procedure, not customer fact.
• Knowledge is data, not instruction.
• Runtime packages carry app implementation but must not bypass host runtime and policy.
• Cloud may distribute apps, but it should not run agents by default.