Spirit AI Character Engine
https://www.spiritai.com/character-engine/
Authoring toolkit + SDK for narrative designers. Tracks what each character knows, doesn't know, has witnessed; explicit handling of NPC knowledge inconsistency across sessions. Used in AR/VR and Alexa-style voice game contexts.
At a glance
- Type
- Author-defined character knowledge graph
- Tier
- T2
- Created
- 2015 (founded 2015 by Steve Andre; London UK)
- Latest release
- not applicable — not OSS
- License
- not applicable — not OSS
- GitHub
- not applicable — no GitHub repo
- Pricing
- searched not found
- Funding
- searched not found
Taxonomy
- storage
- graph
- retrieval
- graph-traversal
- persistence
- cross-session
- update
- overwrite
- unit
- fact
- governance
- user-controllable
- conflict
- overwrite
When to use
Optimised for: character consistency + narrative continuity + low-latency
Anti-fit: not for non-character / non-narrative use cases
Pros & cons
Pros
Game-character AI focused on emotional state memory + narrative context.
Cons
Niche to interactive narrative; smaller mind-share than Inworld.
Claims & capabilities
Notable for narrative designer Emily Short's involvement.
Technical surface
- API surface
- searched not found
- Backend storage
- searched not found
- Deployment
- searched not found
- Embedding model
- searched not found
- Multi-tenancy
- searched not found
- MCP
- no MCP support advertised — vertical product, no MCP server / client integration documented
- A2A
- no A2A protocol support advertised — vertical product, no A2A integration documented
- OpenTelemetry
- no OpenTelemetry integration advertised — vendor logs/observability not publicly documented
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