AI Systems Atlas

H-20Shared Blackboard

/harnesses/shared-blackboard

Agents coordinate by reading and posting to a shared workspace, never by messaging each other; a controller watching it picks who acts next.

Step-by-step walkthrough8 steps
  1. A problem is posted to a shared board. No agent will ever message another.
  2. The controller reads the board and picks who can move it forward: the searcher.
  3. The searcher posts sources. It neither knows nor cares who will use them.
  4. Sources but no hypothesis — so the controller wakes the analyst, which reads everything posted so far.
  5. The analyst posts a hypothesis and an open question for whoever can answer it.
  6. Two agents post to the same slot at once. Without ownership rules, the board now holds a contradiction.
  7. Once the board holds enough, the writer reads it all and drafts.
  8. The controller sees “done” on the board. Agents coordinated through state, not conversation.
Key insight

The board replaces a web of conversations with one piece of state. Agents stay decoupled, any of them can join by reading it, and nothing passes through a supervisor’s context as a lossy summary.

Failure mode

Write contention. Two agents update the same fact at once and the board holds both; without slot ownership or versioning, every later reader inherits the contradiction.

Further reading
RelatedHierarchicalParallel swarmState representationAgent-to-agent trust

Elsewhere in the atlas

Security →Evals →Context →Coding Agents →Tools →Ops →