> The full index of these docs is at [llms.txt](https://u22a8.ai/llms.txt). # Glossary Each term the A8 docs use, defined once, with the page that explains it. Each term below has one meaning across the docs. An entry gives the definition and links the page that covers it. ## Abstention A declined verdict, returned where the evidence falls short of the minimum accuracy the request sets. The abstention’s `kind` names the check the evidence failed. See [Accuracy and abstention](https://u22a8.ai/docs/a8-abstention.md). ## Alias A model identifier that resolves to another. `a8` resolves to your organization’s latest ready horizon on the latest version, and stays on the earlier version until your teaching is refitted on a new one. See [Model identifiers](https://u22a8.ai/docs/a8-model-identifiers.md). ## Assistant The AI assistant you talk to over MCP, such as Claude in Claude Code. It calls A8’s tools for you. See [MCP](https://u22a8.ai/docs/a8-mcp.md). ## Content filter The outcome of a request A8 filtered for harmful content: an outcome apart from a verdict and an abstention, reported in each interface’s own content-filter slot, such as `finish_reason: "content_filter"` in Chat Completions. See [Known limits](https://u22a8.ai/docs/known-limits-a8-1.md). ## Coverage The share of requests A8 answers. Coverage is always reported beside accuracy, which is measured over the answered requests. See [Testing](https://u22a8.ai/docs/a8-testing.md). ## Criterion What is being judged, stated in plain words. The plural is criteria. The system message, or the instructions field of the interface, carries it. See [Writing criteria](https://u22a8.ai/docs/writing-criteria.md). ## Earned level An accuracy level a criterion’s evidence has shown, also called a level. A request’s minimum accuracy lands on the nearest earned level at or above it. See [Accuracy and abstention](https://u22a8.ai/docs/a8-abstention.md). ## Fit Producing a new version of your organization’s model from the examples you taught. Each fit mints a horizon. See [Teaching](https://u22a8.ai/docs/a8-teaching.md). ## Follow-up A user message sent after A8’s response in the same conversation. A8 answers it with the whole conversation in view. See [API overview](https://u22a8.ai/docs/api-overview.md#continue-a-conversation). ## Horizon The timestamp that names a fitted version, such as `20260715t140322z`. See [Horizons](https://u22a8.ai/docs/a8-horizons.md). ## Interface One of the standard APIs A8 answers: Chat Completions, Responses, Anthropic Messages and MCP. See [API overview](https://u22a8.ai/docs/api-overview.md). ## MCP host The application that runs MCP servers, such as Claude, ChatGPT or Cursor. You add A8’s server to it once. See [MCP](https://u22a8.ai/docs/a8-mcp.md). ## Minimum accuracy The accuracy a request asks its verdict to meet, from 0 to 99, 90 by default. A request sets it as the model’s tag, `a8:95`, and the response reports the level it was served at as `min_accuracy` and in its `model`. See [Accuracy and abstention](https://u22a8.ai/docs/a8-abstention.md#minimum-accuracy). ## Model identifier The name of the model that answers a request, such as `a8-1-1:95@20260715t140322z`: a family, a version, the minimum accuracy as its tag, and a horizon. See [Model identifiers](https://u22a8.ai/docs/a8-model-identifiers.md). ## Pin Request a specific version by its full identifier, so its verdicts hold still. See [Horizons](https://u22a8.ai/docs/a8-horizons.md#pinning). ## Precedent A taught example cited behind a verdict. See [Precedents](https://u22a8.ai/docs/a8-precedents.md). ## Provisional horizon The horizon the next fit mints from what you taught so far. The models list shows it with `status: "provisional"` until the fit completes. See [Horizons](https://u22a8.ai/docs/a8-horizons.md#the-provisional-horizon). ## Reasoning How A8 reads a request, switched by each interface’s own reasoning field. On, the default, A8 reads a request however it is laid out, a grader prompt included, and usage reports the reading as reasoning tokens. Off, A8 reads the layout as written: the system message is the criterion and the latest user message the subject. See [API overview](https://u22a8.ai/docs/api-overview.md). ## Recall A8’s answer to “What have I taught you about refunds?”: the taught examples most relevant to the question, word for word. See [Precedents](https://u22a8.ai/docs/a8-precedents.md). ## Reference model The model every organization starts from, as we publish it. Call it directly as `a8-1-1@reference`. See [Horizons](https://u22a8.ai/docs/a8-horizons.md#the-reference-model). ## Retract Remove a taught example, so the next fit uses the examples that remain. See [Teaching](https://u22a8.ai/docs/a8-teaching.md). ## Subject The thing under judgment. The user messages carry it, and a follow-up after A8’s response can change it. See [API overview](https://u22a8.ai/docs/api-overview.md#continue-a-conversation). ## System fingerprint The `system_fingerprint` token on every response. It changes whenever anything behind a verdict moves. See [Reproducibility](https://u22a8.ai/docs/a8-reproducibility.md). ## Teach As a verb, send a request with the answer it should get. As a noun, one such example: “a teach”. The activity is teaching. See [Teaching](https://u22a8.ai/docs/a8-teaching.md). ## Verdict What A8 returns for a subject: a label, a number or a JSON object in the shape the request asks for. See [API overview](https://u22a8.ai/docs/api-overview.md). ## Version A fitted model, named by its horizon. See [Model identifiers](https://u22a8.ai/docs/a8-model-identifiers.md). ## Your organization’s model The model your teaching trains: the reference model plus everything your organization taught. It stays within your organization. See [Teaching](https://u22a8.ai/docs/a8-teaching.md). ## Next steps - [A8 model card](https://u22a8.ai/docs/a8.md): A8 on one page: model IDs, pricing, capabilities, endpoints, features, rate limits and how it compares. - [Accuracy and abstention](https://u22a8.ai/docs/a8-abstention.md): How a request sets the minimum accuracy a verdict must meet, what that level promises and the five kinds of abstention. - [Teaching](https://u22a8.ai/docs/a8-teaching.md): How to teach and retract through MCP, when a teach lands in your organization’s model and what it changes.