Molecules
Concept-level compositions (B3) — the named agentic vocabulary built from primitives.
AgentLoop — think → act → observe (the centerpiece)
step 2
Agentthink
tools
answer
LLMCall
You
Claudeopus-4.8
Response
ToolCall
Claude
read_file
PromptStack
systemYou are a helpful assistant.
userExplain agent loops.
assistantThink, act, observe — repeat.
Claudeopus-4.8
ToolRegistry
Agent
tools available
read_file
run_bash
github
Guardrail — pass / block
You
input
Claude
output
Response
You
input
Claude
output
blocked
MCPConnector
Agentclient
MCPserver
github
MemoryStore
Agent
memory
Router
Router
billing
tech
sales
Skill
Agent
pdf
skill
read · fill · merge PDFsContextWindow
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