A reference from Weave

Find a term

Understand the metrics, models, and methods behind modern engineering. Clear definitions, practical examples, and a closer look at what the numbers actually mean.

Terms beginning with U

17 terms

  • Uncached token

    Uncached token is an input token processed without a reusable cache hit. It gives teams a way to name, measure, or reason about an economic property of an AI workload without treating raw usage as proof of value.

    Token costs and AI ROI

  • Underfitting

    Underfitting is a language-model concept about mechanism and information flow. It names a mechanism, representation, training practice, or operational behavior that can change how an AI system processes input and produces output.

    LLM fundamentals

  • Unified model API

    Unified model API is a model-routing or gateway concept used to manage interface consistency for AI requests. It describes a distinct decision, control, interface, or observation point between an application and one or more model providers.

    Model routing and gateways

  • Unique identifier

    Unique identifier distinguishes an event, entity, or work item in scope.

    Engineering analytics

  • Unit of analysis

    Unit of analysis is a statistical or measurement concept used to describe, compare, or interpret engineering data. Its meaning depends on the unit of analysis, data-generating process, and question being asked.

    Measurement and experimentation

  • Unit of measure

    Unit of measure states what a metric value represents.

    Engineering analytics

  • Unit testing

    Unit testing is the practice of checking a small, replaceable part of a program in isolation from its collaborators. A unit test usually supplies controlled inputs, observes behavior, and compares the result with an expected outcome.

    Code quality and technical debt

  • Unplanned work

    Unplanned work is a developer productivity concept that helps teams understand unplanned work in the context of software delivery.

    Developer productivity

  • Unplanned work rate

    Unplanned work rate is a developer productivity concept that helps teams understand unplanned work rate in the context of software delivery.

    Developer productivity

  • Upstream dependency

    Upstream dependency is a concept used in software delivery planning to describe a condition, relationship, estimate, or decision about engineering work.

    Flow and capacity planning

  • Urgency

    Urgency is a concept used in software delivery planning to describe a condition, relationship, estimate, or decision about engineering work.

    Flow and capacity planning

  • Usability debt

    Usability debt is a software maintenance concern describing a condition that can make future changes, verification, operation, or ownership harder. Its practical importance depends on supported behavior, rate of change, and the consequences of delay.

    Code quality and technical debt

  • Usability testing

    Usability testing is a software testing or test-design practice used to gather evidence about a defined risk, behavior, boundary, or operating condition. It makes the question under test explicit, identifies the inputs and observations that matter, and gives a team a repeatable basis for deciding whether the result is acceptable.

    Code quality and technical debt

  • Usage normalization

    Usage normalization is a model-routing or gateway concept used to manage interface consistency for AI requests. It describes a distinct decision, control, interface, or observation point between an application and one or more model providers.

    Model routing and gateways

  • Use case testing

    Use case testing is a software testing or test-design practice used to gather evidence about a defined risk, behavior, boundary, or operating condition. It makes the question under test explicit, identifies the inputs and observations that matter, and gives a team a repeatable basis for deciding whether the result is acceptable.

    Code quality and technical debt

  • User research

    User research is a way to organize, support, or evaluate software work so that teams can make useful progress with less avoidable friction. It is most valuable when connected to a concrete outcome and the local conditions of the team using it.

    Developer productivity

  • User-visible error

    User-visible error is a reliability concept used to describe a specific condition, control, or decision in the operation of software services.

    Reliability and observability