GitHub Copilot key terms
GitHub Copilot · Get comfortable with the vocabulary.
- Acceptance rate
- Related: Suggestion acceptance, Copilot metrics
The share of Copilot suggestions a developer inserts rather than dismisses. It is a usage signal, not a quality score, and varies widely by language, file type, and task.
- Agent mode
- Related: Edit mode, Copilot Chat, Tool calling
A Copilot Chat mode where the model plans multi-step work, edits multiple files, runs terminal commands, and iterates on errors until the task completes or it needs your approval.
- Attribution
- Related: Public code filter, Duplicate detection filter
A code referencing feature that matches Copilot output against public code so you can see whether a suggestion resembles known licensed or public repository content before accepting it.
- Chat context window
- Related: Context crafting, #-reference, Prompt
The fixed amount of text a model can consider at once, spanning your prompt, attached files, conversation history, and retrieved snippets. Content beyond it is truncated or summarized.
- Code completion
- Related: Ghost text, Next edit suggestions
Inline, ghost-text suggestions generated as you type in the editor. The model predicts the next tokens based on surrounding code, open tabs, and repository context.
- Code referencing
- Related: Attribution, Public code filter, Duplicate detection filter
A Copilot feature that surfaces matches between generated code and indexed public repositories, letting organizations review matches and set whether suggestions with matches are blocked.
- Content exclusion
- Related: Exclusion policy scope, Repository indexing
A repository or organization setting that prevents Copilot from using specified files or paths as context for completions and chat. It reduces exposure but does not fully block all Copilot behavior.
- Context crafting
- Related: #-reference, Chat context window, Prompt
Deliberately selecting what the model sees: open relevant files, reference specific paths, summarize constraints, and remove noise so suggestions match your codebase conventions.
- Copilot Chat
- Related: Agent mode, Edit mode, Slash command
A conversational interface in the IDE, GitHub, and CLI that answers questions, explains code, proposes edits, and can act on the workspace with your approval.
- Copilot metrics
- Related: Acceptance rate, Seat management
Aggregated usage data such as active users, acceptance rates, and feature adoption, available through organization dashboards and APIs for measuring rollout impact.
- Copilot plan tiers
- Related: Seat management, Data retention
Subscription levels such as Individual, Business, and Enterprise that differ in policy controls, audit logs, data retention options, and model access.
- Custom instructions
- Related: Prompt file, Context crafting
A repository or personal file of standing guidance, such as coding standards and preferred libraries, that Copilot applies automatically to chat and generation requests.
- Data retention
- Related: Copilot plan tiers, Telemetry
How long prompts and suggestions are stored. Policies differ by plan and setting, and organizations can often opt out of retention for model training.
- Duplicate detection filter
- Related: Public code filter, Code referencing
A server-side filter that blocks suggestions closely matching public code, reducing the chance of inadvertently reproducing licensed snippets.
- Edit mode
- Related: Agent mode, Copilot Chat
A Copilot Chat mode that proposes coordinated changes across selected files as a reviewable diff, without autonomously running commands or looping on its own.
- Exclusion policy scope
- Related: Content exclusion, Repository indexing
The level at which content exclusions apply, such as organization or repository, and the precedence rules that determine which setting wins when both exist.
- Few-shot prompting
- Related: Prompt, Zero-shot prompting
Including a small number of worked examples in the prompt so the model imitates the desired format, naming style, or pattern rather than guessing.
- Ghost text
- Related: Code completion, Suggestion acceptance
The dimmed inline suggestion shown in the editor before acceptance. It is a preview, not committed code, and can be cycled through with keyboard shortcuts.
- Hallucination
- Related: Human in the loop, Verification
Confident output that is wrong, such as a nonexistent API, package, or parameter. Review and test generated code rather than trusting plausibility.
- Human in the loop
- Related: Hallucination, Verification
The practice of reviewing, testing, and taking responsibility for Copilot output. The developer remains the author and is accountable for correctness, security, and licensing.
- Next edit suggestions
- Related: Code completion, Ghost text
Predictions of the next place your code needs changing after an edit, offered as navigable suggestions rather than only completions at the cursor.
- Prompt
- Related: Prompt engineering, Context crafting
The instruction and supporting context you give Copilot. Its specificity, constraints, and examples strongly shape the relevance and correctness of the response.
- Prompt engineering
- Related: Prompt, Few-shot prompting, Context crafting
Structuring requests with clear goals, constraints, output format, and relevant context so the model produces usable results with fewer correction cycles.
- Prompt file
- Related: Custom instructions, Slash command
A reusable Markdown file of instructions that can be invoked in chat, letting teams standardize recurring tasks such as reviews, test generation, or documentation.
- #-reference
- Related: Context crafting, Chat context window
Chat syntax that attaches a specific file, symbol, or repository element to the prompt, giving the model precise context instead of relying on inferred workspace state.
- Public code filter
- Related: Duplicate detection filter, Code referencing
A setting that suppresses suggestions matching public repositories above a similarity threshold, complementing code referencing and duplicate detection.
- Repository indexing
- Related: Content exclusion, Retrieval
Building a searchable representation of a repository so chat can retrieve relevant files and symbols. Indexing scope interacts with content exclusions and permissions.
- Retrieval
- Related: Repository indexing, Chat context window
Fetching relevant snippets from the workspace or index to place in the prompt, which is how Copilot grounds answers in your code rather than only its training data.
- Seat management
- Related: Copilot plan tiers, Copilot metrics
Assigning, revoking, and auditing Copilot licenses across an organization, including policy assignment and ensuring only authorized users have access.
- Slash command
- Related: Copilot Chat, Prompt file
A shorthand in chat that triggers a built-in workflow, such as explaining code, generating tests, or fixing a problem, without writing a full prompt.
- Suggestion acceptance
- Related: Ghost text, Human in the loop
The act of inserting a Copilot suggestion. Accepting means you own the code, so review it for correctness, security, and style before committing.
- Telemetry
- Related: Data retention, Copilot metrics
Operational and usage data collected about Copilot features. Understand what is collected, where it flows, and how it differs from prompt retention.
- Test generation
- Related: Slash command, Verification
Using Copilot to draft unit tests from a selected function or file, then reviewing edge cases and assertions rather than accepting them blindly.
- Tool calling
- Related: Agent mode, Model Context Protocol
The mechanism by which an agent invokes external capabilities such as search, terminal commands, or MCP servers, with approvals controlling what it may execute.
- Model Context Protocol
- Related: Tool calling, Agent mode
An open protocol for connecting AI assistants to external tools and data sources, letting Copilot access services configured by your organization or team.
- Verification
- Related: Human in the loop, Hallucination
Checking generated code through reading, compiling, running tests, and security review. Passing tests alone does not prove correctness or safety.
- Zero-shot prompting
- Related: Few-shot prompting, Prompt
Asking the model to perform a task with instructions only, no worked examples. It works well for common tasks but is less reliable for strict formats.