Ejentum - Reasoning Harness vs Myco Brain

Ejentum - Reasoning Harness and Myco Brain are both agent frameworks tracked by AIDiveForge. Below is a side-by-side comparison of pricing, capabilities, platforms, and ownership — sourced from each tool's live website and verified before publishing.

Ejentum - Reasoning Harness

The scraped page content provided does not match the tool described in the structured data — it belongs to a travel-identification app called Spotter, not Ejentum's reasoning harness. Based solely on the structured tool data and validator context, Ejentum is positioned as a reasoning layer that wraps agents with auditable decision chains, anti-deception safeguards, and token-optimized reasoning paths. The vendor states it targets competitive programming benchmarks and compliance-grade auditability. Without matching page content to source specific architectural or integration claims, production behavior at scale and exact failure ceilings cannot be confirmed.

Myco Brain

The core mechanic is deterministic writes: the application code writes facts to Myco's Postgres store, not the LLM, so every stored fact carries a source document, a confidence score, and a full audit trail queryable via brain_why. One MCP server exposes that memory to Claude Code, Cursor, Codex, Windsurf, and any other MCP-compatible client simultaneously — write from Claude Desktop, retrieve from Cursor, no sync step required. The vendor publishes a 500-question LongMemEval result and a recall@5 figure using a recency reranker, both on the full benchmark set. The hard ceiling appears when your agents need to act on what they remember — Myco stores and retrieves facts; it does not plan, route, or execute tasks, so orchestration logic lives elsewhere.

Attribute	Ejentum - Reasoning Harness	Myco Brain
Pricing	Paid	Free
Price	€5/month or €25/month	—
Free trial	30 days	No
Open source	No	Yes
Has API	Yes	No
Self-hosted option	No	Yes
Platforms	API (HTTP REST); vendor targets global edge network	Postgres, Docker, MCP clients
Released	—	2026
Pros	Auditable, step-by-step reasoning records for every agent decision, so compliance reviews have a traceable chain rather than a black-box output to defend. Anti-deception safeguards enforce that reasoning steps actually bind the final output, which means you catch the class of agent failure where the scratchpad looks right but the answer diverges. Token-cost optimization built into the reasoning chain, so teams running high-frequency agents avoid paying for verbose intermediate steps that add latency without improving accuracy. API access available, so the reasoning layer drops into an existing agent architecture without forcing a full platform migration. Targets measurable performance benchmarks on competitive programming and reasoning tasks — the vendor states this directly — giving teams a concrete signal for whether the layer is adding reliability, not just overhead.	Deterministic write path means the LLM never authors the facts stored in memory, so every retrieved fact links to a source document and confidence score — which means regulated teams get an audit trail without building one themselves. One MCP server shared across all connected clients, so a fact written from Claude Desktop is immediately readable by a Cursor agent without a sync job or intermediate API call. Full-stack boot with docker compose and no required API keys, so teams evaluate and prototype without committing credentials or cloud spend before the architecture is validated. Content-hash deduplication on document ingestion, so re-importing the same ChatGPT or Claude export twice does not corrupt or inflate the memory store. Graph queries over entity relationships via the built-in tools, so agents can retrieve not just isolated facts but the web of connections between people, decisions, and documents in the store.
Cons	No self-hosted deployment option exists, which means teams with strict data-residency or air-gapped infrastructure requirements cannot use this tool at all — they move to an open-source reasoning framework they can run on their own hardware. Usage-based call limits at the paid tiers create a hard ceiling for high-throughput production agents; teams processing thousands of reasoning calls per hour will exhaust quota before the billing cycle ends and face either throttling or unplanned cost escalation. The tool is a paid-only feature beyond the free trial period — teams that build a production dependency during the trial face a forced upgrade decision with no self-hosted fallback, which makes budget approval a blocker for continued use.	Myco stores and retrieves facts — it has no planner, no task router, and no execution loop. Teams building agents that need to act on retrieved memory must implement that logic themselves, which means maintaining a separate orchestration layer alongside the memory layer. The self-hosted path requires running Postgres 16 with pgvector and managing that infrastructure. Teams without existing Postgres ops experience hit configuration and maintenance overhead that the single docker compose up does not eliminate long-term. Semantic search requires a local Ollama instance or an external embedding provider; teams without GPU-capable self-host infrastructure who want semantic recall beyond full-text search are blocked until the cloud offering exits beta — at which point they are evaluating a hosted product with a waitlist rather than a drop-in replacement. No API surface is exposed outside the MCP protocol, so teams whose agents run outside MCP-compatible clients cannot integrate without building a custom MCP wrapper — teams with that constraint typically move to a vector database with a standard REST or gRPC API instead.

Bottom line

Ejentum - Reasoning Harness is paid while Myco Brain is free; Myco Brain is open source; only Ejentum - Reasoning Harness exposes a public API. Choose based on which difference matters most for your workflow.

Frequently asked questions

What is the difference between Ejentum - Reasoning Harness and Myco Brain?

Ejentum - Reasoning Harness is Paid, while Myco Brain is Free and open source. Compare pricing, free trial, API, platforms, and pros/cons in the table above on AIDiveForge.

Is Ejentum - Reasoning Harness better than Myco Brain?

It depends on your workflow. Use the side-by-side attributes (pricing, open source, API, self-hosted, platforms) to decide. AIDiveForge does not rank a universal winner — we publish verified facts so you can choose.