Centroid definition
The Default MCP Memory Server
Definition
The default MCP memory server is a local-first tool built as a primary MCP server, installed with a single command, that captures AI coding session context and persists it across sessions using embedded storage.
The centroid is defined from 20 in-cluster projects, not all 32 repositories. Adjacent infrastructure is analyzed separately so it does not distort the default pattern.
Denominator: in-cluster, N=20. Source: Manual-audit/CENTROID-MCP-MEMORY-32.md. Reader meaning: the centroid defines the sector default used for public comparison, not an ideal product or recommendation.
Sector Boundary
The centroid applies to repositories whose primary product is an MCP memory server. Knowledge graph engines, enterprise memory platforms, agent runtimes, reference implementations, and edge cases remain visible in the full corpus but do not define the centroid denominator.
Centroid Traits
| Trait | Prevalence | Description |
|---|---|---|
| C1 MCP-primary | 95% | Primary product is an MCP server. |
| C2 Session continuity | 95% | Core purpose is session-to-session persistence. |
| C3 Embedded storage | 65% | SQLite, ChromaDB, DuckDB, or similar. |
| C5 Local-first | 75% | No cloud dependency for core functionality. |
| C6 Context-loss opening | 65% | README opens with AI-forgets framing. |
| C7 Persistence vocabulary | 90% | Uses persistent, memory, context, session, or recall vocabulary. |
| C8 Single-command install | 70% | npx, pip, brew, or equivalent. |
| C9 Single-developer | 80% | Top contributor dominates commit history. |
| C10 Recent creation | 75% | Less than one year of active development. |
Dropped Trait
Text/keyword search as the primary retrieval method dropped to 25% prevalence in the expanded corpus, below the threshold for centroid inclusion. The sector has diversified into keyword-primary, semantic-first, hybrid, and no-search approaches.
Validation
The two-pass denominator protects the centroid from adjacent-category noise: the full corpus is N=32, but trait prevalence is calculated against the 20 retained MCP memory servers. A trait needs majority prevalence in that in-cluster sample to define the public centroid.
Source Artifacts
The centroid page is derived from the accepted centroid, visual-data, calibration, and public report artifacts. Found a stale repo, wrong source trace, or boundary classification issue? Send a correction to hello@diversum.dev with the repo name, displayed value, and replacement source.
| Artifact | Source Role | Visible Metric Families |
|---|---|---|
| Manual-audit/CENTROID-MCP-MEMORY-32.md | Centroid trait counts and denominator | Definition, traits, dropped trait, validation. |
| Reports/VISUAL-DATA.md | Chart-ready centroid prevalence | Trait percentages and display context. |
| Manual-audit/CALIBRATION-TABLE-RADAR.md | Per-repo role and score derivation | Boundary separation and score context. |
Corrections
If a centroid trait, denominator, or boundary classification looks stale, contact hello@diversum.dev with the page section, repo or trait name, displayed value, and source evidence for review.