zeph-context 0.20.0

Context budget, manager, compaction strategy, and assembler for the Zeph agent
Documentation

zeph-context

Context budget, lifecycle management, compaction strategy, and stateless context assembler for the Zeph AI agent.

This crate contains the stateless and data-only parts of context management extracted from zeph-core. It has no dependency on zeph-core — callers implement the IndexAccess trait and populate ContextMemoryView before each assembly pass.

Modules

  • budget — ContextBudget and BudgetAllocation for token budget calculation
  • manager — ContextManager state machine and CompactionState lifecycle tracking
  • assembler — ContextAssembler parallel fetch coordinator; classifies each slot into a TypedPage, enforces per-type fidelity invariants at compaction boundaries, and emits a CompactionAuditSink record per compacted page
  • input — ContextAssemblyInput, ContextMemoryView, IndexAccess trait
  • slot — ContextSlot, CompactionOutcome, message-chunking helpers
  • typed_page — TypedPage (BLAKE3 content-hash id), PageType enum (ToolOutput, ConversationTurn, MemoryExcerpt, SystemContext), per-type PageInvariant implementations, and InvariantRegistry
  • audit — CompactionAuditSink — bounded async mpsc channel that records one audit entry per compacted page; consumers can drain it for observability or compliance logging
  • error — ContextError

ClawVM typed-page compaction

ContextAssembler::gather() classifies every context slot into a TypedPage keyed by a BLAKE3 content hash. Each PageType carries a PageInvariant that declares the minimum-fidelity guarantee for compaction:

PageType Invariant
ToolOutput Preserve tool name, return code, and first/last N bytes of output
ConversationTurn Preserve role, first sentence, and any code blocks
MemoryExcerpt Preserve entity names and relationship predicates
SystemContext Never compact — always injected verbatim

At every compaction boundary the invariant is checked before the LLM compaction call. If the post-compaction result would violate the invariant the compaction is rejected and the original content is retained.

License

MIT OR Apache-2.0