This release fixes issues for SREs watching stability and regressions.
✓ No known CVEs patched in this version
Topics
Affected surfaces
Summary
AI summaryFixed multiple stability bugs in the async post‑processor and related pipelines.
Changes in this release
| Type | Severity | Summary | CVE |
|---|---|---|---|
| Dependency | Medium |
All @mcpfusion/* cross-dependencies updated to ^4.0.1 synchronizing monorepo packages on version 4.0.1. All @mcpfusion/* cross-dependencies updated to ^4.0.1 synchronizing monorepo packages on version 4.0.1. Source: granite4.1:8b-q6_K@2026-05-20 Confidence: low |
— |
| Performance | Medium |
Presenter Performance Optimization implements a single-pass executePipelineWithData loop, avoiding redundant Zod validation and reducing serialization overhead. Presenter Performance Optimization implements a single-pass executePipelineWithData loop, avoiding redundant Zod validation and reducing serialization overhead. Source: granite4.1:8b-q6_K@2026-05-20 Confidence: high |
— |
| Performance | Medium |
O(1) Cache Staleness Detection integrates description-based cache invalidation in StateSyncLayer via non-enumerable descriptor tagging, ensuring clean cache invalidation for dynamic registrations and hot-reloads. O(1) Cache Staleness Detection integrates description-based cache invalidation in StateSyncLayer via non-enumerable descriptor tagging, ensuring clean cache invalidation for dynamic registrations and hot-reloads. Source: granite4.1:8b-q6_K@2026-05-20 Confidence: high |
— |
| Bugfix | Medium |
Async PostProcessor Migration converts postProcessResult to support fully asynchronous Presenter callback execution without losing context or dropping UI/rule blocks. Async PostProcessor Migration converts postProcessResult to support fully asynchronous Presenter callback execution without losing context or dropping UI/rule blocks. Source: granite4.1:8b-q6_K@2026-05-20 Confidence: high |
— |
| Bugfix | Medium |
Priority 0 Handoff Guard enforces explicit HandoffResponse priority inside PostProcessor to prevent serialization crashes on content-block extraction layer. Priority 0 Handoff Guard enforces explicit HandoffResponse priority inside PostProcessor to prevent serialization crashes on content-block extraction layer. Source: granite4.1:8b-q6_K@2026-05-20 Confidence: high |
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| Bugfix | Medium |
Grouped-mode FSM Gates harden tool routing inside ServerAttachment to enforce action-qualified canonical names when matching tool calls against FSM rules. Grouped-mode FSM Gates harden tool routing inside ServerAttachment to enforce action-qualified canonical names when matching tool calls against FSM rules. Source: granite4.1:8b-q6_K@2026-05-20 Confidence: high |
— |
| Bugfix | Medium |
EgressGuard Boundary Remediation refines byte-limit truncation logic to reliably append truncation suffixes at block boundary budgets. EgressGuard Boundary Remediation refines byte-limit truncation logic to reliably append truncation suffixes at block boundary budgets. Source: granite4.1:8b-q6_K@2026-05-20 Confidence: high |
— |
| Refactor | Medium |
Code Cleanliness & Test Sanitization replaces legacy regression test files with standardized behavior-oriented unit tests, removing technical debt comments and bug tracking references. Code Cleanliness & Test Sanitization replaces legacy regression test files with standardized behavior-oriented unit tests, removing technical debt comments and bug tracking references. Source: granite4.1:8b-q6_K@2026-05-20 Confidence: low |
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Full changelog
Fixed
@mcpfusion/core — Engine Stability & Pipeline Hardening
- Async PostProcessor Migration — Converted
postProcessResult()to support fully asynchronous Presenter callback execution (asyncUiBlocks,asyncRules,asyncSuggestActions,PromptFirewall) without losing context or dropping UI/rule blocks in downstream pipelines. - Presenter Performance Optimization — Implemented a single-pass
executePipelineWithDatapipeline execution loop. This avoids redundant Zod validation and ensures deterministic execution of non-idempotent Zod transforms (z.transform()), reducing serialization overhead. - Priority 0 Handoff Guard — Enforced an explicit
HandoffResponsepriority guard insidePostProcessorto intercept swarm handoff events and prevent serialization crashes on the content-block extraction layer. - O(1) Cache Staleness Detection — Integrated description-based cache invalidation inside
StateSyncLayervia non-enumerable descriptor tagging (_srcDesc). Ensures dynamic registrations and hot-reloads invalidate caches cleanly. - Grouped-mode FSM Gates — Hardened tool routing inside
ServerAttachmentto enforce action-qualified canonical names (group.action) when matching tool calls against FSM rules, fixing potential transition bypasses. - EgressGuard Boundary Remediation — Refined byte-limit truncation logic to reliably append truncation suffixes when the payload exactly matches block boundary budgets.
- Code Cleanliness & Test Sanitization — Replaced all legacy regression test files with standardized, behavior-oriented unit tests (
PostProcessorAsync.test.ts,StateSyncStaleness.test.ts), completely removing technical debt comments and bug tracking references.
Changed
- All
@mcpfusion/*cross-dependencies updated to^4.0.1— All monorepo packages now synchronize on version4.0.1.
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About vinkius-labs/mcp-fusion
A TypeScript framework for building production-ready MCP servers with automatic tool discovery, multi-transport support (stdio/SSE/HTTP), built-in validation, and zero-config setup.
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