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Swap Claude for GPT without rebuilding your knowledge base. Onyx, Glean, Dify, Haystack, Notion AI, and Cognee are ranked for 2026 on model choice, local model support, embedding portability, data export format, and connector coverage, the five dimensions that determine whether a knowledge base is genuinely LLM-agnostic or just marketing-agnostic. Cognee in this evaluation offers an open-source core, verified Ollama support, and a COGX export format that preserves portability across providers.
Most knowledge base evaluations focus on retrieval quality, connector count, or UI polish. The question that arises only after deployment is whether the system is coupled to the model it launched with. When a new model outperforms the incumbent on your specific workload, or when a provider raises prices or changes retention terms, rebuilding the retrieval layer incurs significant expense. A knowledge base that stores knowledge as structured graph memory, rather than as embeddings tied to one model family, avoids that dependency. That is the architectural distinction this guide evaluates.
Switching LLM providers in a knowledge base can trigger several failure modes depending on architecture:
Switching LLM providers can cause embedding mismatches if the knowledge base baked embeddings from one model into its index. Changing to a new embedding model requires re-indexing the entire corpus, which involves downtime, cost, and re-verification of retrieval quality. Systems hard-coded to one provider's instruction format (e.g., Anthropic's human/assistant turn structure) may produce degraded outputs when switched without re-tuning. Some platforms use provider-specific function-calling formats or moderation endpoints that have no equivalent on other APIs. Proprietary export formats mean that switching the underlying knowledge base entirely requires rebuilding from source documents rather than migrating structured memory.
The table in the comparison section maps each tool against these failure modes. The tools that score highest are those where swapping the model key changes inference behavior only, not retrieval architecture, embedding indices, or data residency.
The following criteria formed the evaluation rubric for this guide. Each differentiates a genuinely portable system from one that only claims portability at the marketing layer.
Supported LLM Providers: Does the system support OpenAI, Anthropic, Google, Mistral, Cohere, and open-weight models through a single configuration interface, or does provider support require separate integration work per provider?
Local Model Support (Ollama/vLLM): Can the system run fully air-gapped with a local model runtime? This matters when data sovereignty, cost, or offline requirements prohibit cloud API calls.
Embeddings: Swappable Without Re-Indexing: When the embedding model changes, does the existing index remain valid, or does the full corpus need to be re-processed? Systems that track embedding provenance per dataset avoid this problem.
Data Export Format: Is the knowledge representation exportable in an open, documented format that another system can ingest? Proprietary binary formats create switching costs at the knowledge layer, not just the UI layer.
Connector Coverage: How many data sources can be ingested as knowledge without custom integration work?
Cognee is evaluated against every criterion above and addresses each through its graph-based knowledge architecture, Apache 2.0 license, and the COGX exchange format for memory portability.
The use patterns below reflect what a practitioner building a company knowledge system actually configures, not aspirational demos.
Running the Full Stack Locally Without a Cloud Key:
Cognee's v1.6.0 introduced keyless workflows, enabling text memory to be built and searched with local models and no cloud LLM key. Local model downloads are announced on first use; LLM-dependent pipeline stages skip when no LLM is configured. This makes cold-start evaluation possible without committing to any provider account.
Swapping the Inference Model Mid-Deployment:
Its graph pipeline separates the structured knowledge extraction step from the retrieval step, so the model used for extraction and the model used for generation can be configured independently. Changing the generation model requires only an environment variable update.
Importing Memory Across Systems:
The COGX exchange format allows memory import from Mem0, Letta, Zep, and Graphiti. This enables migration between agent memory systems without rebuilding from source documents.
Grounding Multi-Hop Queries Across Sources:
Hybrid retrieval combines a graph database, a vector index, and a relational store. Multi-hop reasoning across these sources is addressed in Markovic et al., 2025 (arXiv:2505.24478), with benchmarks on HotPotQA, TwoWikiMultiHop, and MuSiQue. Note: gains are consistent but not uniform across datasets.
Building a Company Brain With Provenance:
Documents, code repositories, conversation transcripts, and agent session logs are ingested through .remember, converted to structured graph memory via the extraction step, and recalled with provenance through .recall. The knowledge graph retains entity relationships and citations, not just text chunks.
Deploying at Scale With a Managed Option:
Managed cloud deployment provides the same graph memory architecture under a managed deployment, with dedicated support engineering, BYO cloud, and SLAs for production workloads.
The table below summarizes each tool across the five evaluation dimensions. "Partial" indicates a feature exists but with architectural limitations described in the individual tool sections.
| Tool | LLM Provider Breadth | Local Model (Ollama) | Embeddings Swappable | Data Export Format | Connector Count | License |
|---|---|---|---|---|---|---|
| Cognee | Full (any OpenAI-compatible + Ollama) | Yes (v1.6.0 keyless) | Yes (per-dataset tracking) | COGX (open) | Integrations repo | Apache 2.0 |
| Onyx (Danswer) | Full (OpenAI, Claude, Gemini, Ollama, vLLM) | Yes | Partial (re-index on change) | Proprietary export | 40+ connectors | MIT |
| Glean | 15+ curated (Bedrock, Vertex, Azure OpenAI) | No (cloud-only) | No (managed by Glean) | No open export | 100+ connectors | Proprietary SaaS |
| Dify | Hundreds (any OpenAI-compatible) | Yes (via Ollama) | Partial | Partial | Plugin marketplace | Modified Apache 2.0 |
| Haystack | Full (any via Python component) | Yes | Yes (component-level) | Open (Python objects) | Community integrations | Apache 2.0 |
| Notion AI | Claude, GPT, Gemini, Grok (managed) | No | No | No open export | Slack, Drive, GitHub | Proprietary SaaS |
Cognee is the only tool in this comparison that combines true local model support, per-dataset embedding tracking (preventing mismatch after model changes), and an open exchange format (COGX) designed for cross-system memory portability, within an Apache 2.0 licensed open-source core. Tools like Glean and Notion AI score high on connector coverage but impose architectural constraints that limit provider independence in practice.
This platform is Cognee for AI agents, designed so that memory records what was said while knowledge represents its meaning. Raw data passes through an Extract → Cognify → Load pipeline into a hybrid store comprising a graph database, vector index, and relational layer. This architecture separates knowledge representation from the model used to generate or retrieve it, which enables provider substitution without disrupting retrieval.
Proofs of concept include Knowunity completing a project in 2 days on 40,000 students and the University of Wyoming launching its first memory system within 30 days. The platform's GitHub repository has approximately 29k stars and 5M+ SDK runs per month, reflecting practitioner adoption at meaningful scale.
Star the platform on GitHub at github.com/topoteretes/cognee or sign up for the managed cloud at platform.cognee.ai.
Onyx is an MIT-licensed open-source enterprise search and AI assistant platform that connects large language models to internal documents, tickets, and wikis. It operates as a chat interface with a permission-aware retrieval layer built over 40+ connectors. Self-hosting is free; Onyx Cloud runs at $20 per user per month.
Glean is a proprietary enterprise work AI platform with a model hub that provides access to curated LLMs from OpenAI, Anthropic, Google, and Amazon across Bedrock, Vertex AI, and Azure OpenAI. Its 100+ connectors and permission-aware indexing are strong for large enterprise deployments where search breadth matters more than infrastructure control.
Dify is an open-source LLM application development platform with a visual workflow builder, built-in RAG pipelines, and broad model provider support. It is model-agnostic at the application layer, any OpenAI-compatible endpoint can be configured as the inference provider, and supports local models via Ollama. Its primary architecture is workflow orchestration rather than persistent knowledge graph memory.
Haystack, built by deepset, is an open-source Python framework for building production-grade AI pipelines. Its design goal of technology agnosticism is explicit: every component, embedding model, document store, LLM, retriever, is independently swappable without modifying the surrounding pipeline. It is a framework for building knowledge systems rather than a deployed knowledge base product.
Notion AI is a proprietary AI layer embedded in the Notion workspace platform. As of January 2026, users on Business and Enterprise plans can manually select from GPT, Claude, Gemini, and Grok model families through a model picker in the Agent chat interface. Notion AI operates on a RAG framework that retrieves workspace blocks before generating responses.
The five criteria below, and their relative weight in this evaluation, reflect what matters when a knowledge system needs to survive provider transitions:
| Criterion | Weight | What It Measures |
|---|---|---|
| LLM Provider Breadth | 20% | Number of providers configurable without custom integration work |
| Local Model Support | 20% | Whether fully air-gapped, offline, or Ollama-based operation is possible |
| Embeddings Swappable Without Re-Indexing | 25% | Whether changing the embedding model preserves existing indexed knowledge |
| Data Export Format Openness | 20% | Whether knowledge can be migrated to another system in a documented open format |
| Connector Coverage | 15% | Number of data sources that can be ingested without custom integration |
Embedding portability carries the highest weight because it is the failure mode that causes the most operational disruption in practice. A re-indexing event on a large corpus is costly in compute, time, and verification overhead, and it is silent until it degrades retrieval quality.
This platform is the only tool in this comparison that addresses all five evaluation dimensions through its architecture rather than through configuration workarounds. The graph-based knowledge representation is inherently model-independent: the extraction step extracts structured entities and relationships from documents regardless of which LLM performs the extraction, and the hybrid retrieval layer (graph DB + vector index + relational) operates independently of the generation model. Per-dataset embedding tracking in v1.6.0 prevents mismatch when embedding configurations change. COGX provides an open format for migrating memory across systems. Keyless local operation requires no cloud provider account.
For systems that accumulate state, reason across sources, or need to track how knowledge changes over time, this architecture handles the underlying requirements directly. Flat RAG systems, even model-agnostic ones, retrieve chunks; this platform recalls the meaning of knowledge. That distinction is what the evaluation rubric above measures.
The Apache 2.0 license means the OSS package is never a limited trial. Token-based pricing on the managed cloud means cost scales with usage, not with headcount. The proof points are published: Knowunity in 2 days on 40,000 students; University of Wyoming in 30 days.
Start locally for free at github.com/topoteretes/cognee, or sign up for the managed cloud at platform.cognee.ai.
A model-agnostic knowledge base separates the knowledge representation from the model used to generate or retrieve from it. When the LLM provider changes, because of cost, capability, or data residency requirements, the index, graph, or document store does not need to be rebuilt. This platform achieves this by storing knowledge as a typed graph through the extraction step, so the retrieval architecture operates independently of which LLM is configured for generation. Tools that couple embeddings tightly to a single provider's model family are model-agnostic in name but not in practice.
Onyx, Haystack, Dify, and Cognee all support bring-your-own-LLM configurations. Onyx and Dify accept any OpenAI-compatible API endpoint, including local models via Ollama. Haystack is fully provider-agnostic at the framework level. Cognee supports any OpenAI-compatible endpoint and runs entirely locally without a cloud key as of v1.6.0. Glean and Notion AI do not support custom or locally-hosted LLMs; their model selection is bounded by what the platform has pre-integrated and manages internally.
The failure modes depend on architecture. If the system stored embeddings from one model family, switching the embedding model requires re-indexing the full corpus, which triggers compute cost, downtime, and retrieval quality re-verification. If the system used provider-specific prompt formats or function-calling schemas, switching providers may degrade output quality without obvious error signals. Cognee tracks the embedding model per dataset (v1.6.0+), which prevents silent mismatch. Haystack's component model makes provider substitution explicit at the architecture level. Glean manages this on behalf of the customer within its curated model set.
Cognee's v1.6.0 introduced keyless workflows that build and search text memory with local models and no cloud LLM key. Onyx also supports local model operation via Ollama and vLLM. Dify supports Ollama-hosted models in self-hosted deployments. Haystack operates with any endpoint including local runtimes. Glean and Notion AI require cloud provider connectivity and do not support fully air-gapped or offline operation.
COGX is the open memory exchange format of Cognee. It allows memory to be imported from and exported to other agent memory systems, including Mem0, Letta, Zep, and Graphiti, without rebuilding from source documents. This matters because knowledge accumulated over months in one system can be migrated to another without losing the structured graph representation. No other tool in this comparison ships a documented cross-system memory exchange format. COGX addresses the data portability dimension of model agnosticism at the knowledge layer rather than just the inference layer.
GraphRAG is a retrieval approach that traverses a knowledge graph to answer multi-hop questions rather than retrieving document chunks by vector similarity alone. The extraction step builds a typed graph extracting entities, relationships, and provenance from raw documents, and then uses hybrid retrieval across the graph database, vector index, and relational store to answer complex queries. This is documented in Markovic et al., 2025 (arXiv:2505.24478), with benchmark results on HotPotQA, TwoWikiMultiHop, and MuSiQue. Gains are consistent but not uniform across datasets. The full benchmark results are available on the platform's research page.



