| Term | Definition | Home page |
|---|---|---|
| Access plane | The part of Records that applies your own access rules to each person at request time: your identity provider, your HR directory, and your system of record’s security groups and business-unit access. Every access change is audited. | Access plane |
| Acting principal | The person in your org that a server-side request acts for, sent in X-Nexio-Acting-Principal. It narrows what the API key allows. | Authentication |
| Action ledger | The append-only, per-organization record of governed write commands, from which current state is read back. | Writes and the action ledger |
| Annotation | A rating and comment a person leaves on a run, on one part of its output, or on a conversation turn. | Outcomes and annotations |
| API key | The bearer credential on every request. It proves your org and one environment. There are two kinds: organization keys and scoped keys. | Authentication |
| Attachment | A file an end user adds to one turn of a conversation. | Attachments |
| Branch | One path through a conversation’s messages, created when a user edits a message they already sent. | Branching |
| Cancelled | A terminal run status: a cancel request stopped the run before it finished. | Runs |
| Capability | One permission a scoped key carries, such as runs:write or records:read. | Authentication |
| Catalog | The read routes under /api/v1/catalog over served data, with citations to the source documents. | Served data |
| Citation | A pointer from a served value to the document, and where known the page and region, it came from. | Served data |
| Command | One governed write, such as note.create or task.complete, sent with its own idempotency key and appended to the action ledger. | Writes and the action ledger |
| Connection | A configured link to one of your systems, such as a document library, a warehouse, a database, an API or an MCP server. Nexio operates it for you. | Connections |
| Conversation | One end user’s exchange with a conversation instance: its messages, tool events and guardrail events. | Conversations |
| Conversation instance | A configured assistant: instructions, tools, data access and guardrails, released as immutable versions. | Conversations |
| Current read | How Records reads of connected data run: live against the warehouse’s current data at request time, not held to a fixed instant, with the exceptions listed on Completeness and errors. serving.as_of records when it ran, and source changes can show between statements and between pages. | Completeness and errors |
| Defensibility packet | A customer-safe record of how a run’s answer was sourced. | Defensibility and trace |
| Degraded | A terminal run status: the run finished with a usable answer, but part of it could not be produced, and the output says which part. | Runs |
| Diagnostic | A structured, non-fatal note on a run’s output about input quality or a step that could not complete. | Runs |
| Effect | An action a subscription can take when an event matches, such as starting a run or sending a webhook. | Automations |
| Engine | A configured capability that takes a typed input and returns a typed output. It has a stable slug, a type, a draft configuration and released versions. | Engines |
| Engine configuration | The JSON that defines an engine’s behavior. Saving it changes the draft; runs use it once you publish a version, except three settings read from the saved configuration. | Configuration and contract |
| Engine contract | The description of what an engine accepts and returns, shown on the engine’s Contract page in the portal. | Configuration and contract |
| Engine type | The kind an engine belongs to, which defines how it runs, how its configuration is validated and its schemas. Nexio ships a fixed set: comparison, matching, entity_analysis, diligence, triage and opportunity. | Engines |
| Engine version | An immutable, released snapshot of an engine’s configuration, numbered major.minor. A run records the version it used. | Versions and releases |
| Enrichment source | A third-party data source that Nexio operates and an engine can consult during a run. | Connections |
| Environment | A partition of traffic inside your org: one live environment and up to 5 sandboxes. | Environments |
| Eval set | A fixed set of reference cases used to measure an engine or assistant before a new version is released. | Evaluation |
| Extraction | Reading typed facts, each with a quote from its source, out of a document. | Indexing and extraction |
| Extraction pass | A step that reads typed facts, each with a quote, from one class of document. A document is routed to a pass by its class. | Indexing and extraction |
| Family | One named dataset on a plane, with a serve grain and a declared column set. Records reads any registered family through one route. | Families |
| Idempotency key | A value you send in Idempotency-Key so that a retried request returns the original result instead of repeating the work. | Requests and errors |
| Indexing profile | The routing that decides which extraction pass reads each document class for a connection. A connection without its own uses the built-in profile. | Indexing and extraction |
| Ingest source | A registered sender that may post events into your org, authenticated per source with a signature or, for an ams360_ons source, a shared code. | Inbound events |
| Lens | A read-only view of another person’s data, requested with X-Nexio-Records-Lens by a caller whose own scope is All or Platform. | Authority and scope |
| Org | Your organization in Nexio: the boundary for data, API keys and engines. | Introduction |
| Organization key | An API key issued in the portal for one environment, shaped nx_<environment slug>_.... | Authentication |
| Outcome | An event your system reports about what happened after a run, such as a person accepting or overriding its answer. | Outcomes and annotations |
| Output | What an engine produces for a run, returned in the run’s output field. | Runs |
| Plane | One source schema that Records reads, holding a set of families. | Records |
| Platform event | An append-only record of a state change in your org, such as a sync finishing or a document changing. | Platform events |
| Posture | The organization’s access-plane setting (dark, shadow or lit) that decides where a person’s authority comes from. | Authority and scope |
| Profile | A documentation label, not an API object: one configured instance of the platform’s primitives. | Platform model |
| Records | The platform’s typed, authorized read and write layer over a connected system of record. Routes live under /api/v1/records. | Records |
| Register | A paged, filterable list over one kind of record. Most registers also return totals and facets counted over the same authorized base population, and each sets its own facet filters; the activity register returns neither. | Registers |
| Request bounds | The size and shape limits a run request must fit: string length, array items, object fields, depth and total bytes. | Limits |
| Review | A person checking work in the portal: extracted facts before they are trusted, or engine runs. | Review |
| Run | One execution of an engine on one request. | Runs |
| Run cap | An optional monthly limit on how many runs your org can create. | Limits |
| Run status | Where a run is: queued, processing, or one of the terminal values completed, degraded, failed, cancelled. | Runs |
| Sandbox | An environment of kind sandbox, for building and testing. | Environments |
| Sandbox fixture | A test scenario that drives a run of the fixture engine to a chosen terminal state with no provider calls. | Sandbox fixtures |
| Scope | The records a person may read, resolved before a Records read runs. | Authority and scope |
| Scoped key | An API key issued by Nexio, shaped nxsk_v1_..., bound to one environment, a set of engines and a set of capabilities. | Authentication |
| Seat | A person’s authority in one organization, derived at request time from your own systems. | Access plane |
| Served data | Typed, versioned records Nexio extracts from a connection’s documents, effective-dated and carrying citations to the source documents. | Served data |
| Slug | A short, URL-safe identifier, such as an engine slug (vendor-review) or an environment slug (dev). | Engines |
| Subscription | A rule Nexio runs for your org: when a matching event arrives, perform an effect. | Automations |
| Supersession | A corrected result attached to a run that already finished. | Defensibility and trace |
| System of record | The system your organization treats as the source of truth for its records. Nexio reads it, mostly through a replica in your warehouse, and does not write to it. | Records |
| Trace ID | A 32-character hex identifier for one request, stamped on a run as trace_id and returned in x-request-id when you did not send your own request ID. Quote it to support. | Requests and errors |
| Turn | One exchange in a conversation: a user message and the answer the assistant streams back. | Turns and streaming |
| Verification tier | How strongly a delivered fact is backed: checked by a person, agreed by two models, or read once. | Review |
| Webhook | A signed HTTP call Nexio sends to your endpoint, for example when a run finishes. | Webhooks |
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Glossary
Look up any term used in these docs, with a link to the page that explains it.
Each platform term is defined once here and explained on its home page.
Last modified on September 25, 2026