Append-Only Thought Stream

Problem

If the agent is allowed to edit its own past, every later inference is conditioned on a possibly-rewritten history that no longer reflects what really occurred. Audit becomes meaningless because the trail can be rewritten at will. Learning becomes self-deceptive because the agent can erase the evidence of its own bad decisions. Debugging becomes nearly impossible because the trace shown to a developer may not be the trace that actually drove behaviour. Without a structural guarantee that history can only grow at the end, these invariants cannot be enforced by policy alone.

Solution

Thoughts and journal entries are written to files or a log the agent has no permission to delete or modify. Compaction creates new summary files at higher tiers without touching originals. Redaction goes through an explicit operator path, not the agent.

When to use

• You need a guarantee that the agent cannot rewrite its own past reasoning.
• Audit, governance, or trust requirements demand an immutable history.
• Compaction can be implemented as new summary tiers without touching originals.