Merge remote-tracking branch 'origin/ralph/gapfill-docgen'

# Conflicts:
#	configs/codereview_2config.sh
#	configs/selected_benchmark_tasks.json
#	prd.json

Author: LoCoBench Bot

benchmarks/ccb_docgen/docgen-api-001/environment/Dockerfile

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+FROM ubuntu:22.04
+
+# Install dependencies
+RUN apt-get update && apt-get install -y \
+    git \
+    ca-certificates \
+    && rm -rf /var/lib/apt/lists/*
+
+WORKDIR /workspace
+
+# Clone VS Code repository with blobless clone for faster setup
+# Commit 69d110f2 is from main branch (2026-02-16)
+RUN git clone --filter=blob:none --no-checkout https://github.com/microsoft/vscode.git repo \
+    && cd repo \
+    && git checkout 69d110f2fe9decdf0b4f79f894f23b3c1967bcb2 \
+    && git sparse-checkout init --cone \
+    && git sparse-checkout set src/vs/vscode.d.ts src/vs/workbench extensions \
+    && git checkout
+
+# Set working directory to repo root so agent can explore the codebase
+WORKDIR /workspace/repo
+
+# Entry point: agent will generate documentation.md in /workspace/
+CMD ["/bin/bash"]

benchmarks/ccb_docgen/docgen-api-001/instruction.md

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+# Task: Generate VS Code Diagnostic API Reference Documentation
+
+## Objective
+
+Generate comprehensive API reference documentation for the **VS Code Diagnostic API**. The Diagnostic API allows extensions to report code issues (errors, warnings, information, hints) to users within the editor.
+
+## Scope
+
+Your documentation should cover the following API surface within the `vscode.languages` namespace:
+
+### Core Interfaces and Classes
+
+1. **Diagnostic class**: Represents a single diagnostic (error, warning, info, hint)
+2. **DiagnosticCollection interface**: Container for managing diagnostics across documents
+3. **DiagnosticSeverity enum**: Severity levels (Error, Warning, Information, Hint)
+4. **DiagnosticRelatedInformation class**: Additional context for diagnostics
+5. **DiagnosticTag enum**: Tags for categorizing diagnostics (Unnecessary, Deprecated)
+
+### Key Functions
+
+1. **createDiagnosticCollection()**: Factory function for creating diagnostic collections
+2. **getDiagnostics()**: Retrieve diagnostics for a resource or workspace
+
+### Events
+
+1. **onDidChangeDiagnostics**: Event fired when diagnostics change globally
+
+## Required Content
+
+Your API reference must include:
+
+### For Each API Method/Function:
+- **Signature**: Full TypeScript signature with parameter types and return type
+- **Parameters**: Description of each parameter, including optional/required status
+- **Return value**: Description of what is returned
+- **Behavior notes**: How the API behaves in different scenarios
+- **Error cases**: What errors can occur and when
+
+### For Each Interface/Class:
+- **Properties**: All properties with types and descriptions
+- **Methods**: All methods with signatures and behavior
+- **Constructor**: Construction pattern (if applicable)
+- **Lifecycle**: Object lifecycle and disposal semantics
+
+### Usage Examples:
+- **Basic usage**: Simple diagnostic creation and publishing
+- **Advanced patterns**: Event subscription, cleanup, related information
+- **Real-world patterns**: Extract usage examples from internal VS Code code
+
+## Output Format
+
+Write your documentation to `/workspace/documentation.md` using Markdown format.
+
+Structure your documentation as follows:
+
+```markdown
+# VS Code Diagnostic API Reference
+
+## Overview
+[Brief introduction to the Diagnostic API]
+
+## Core Types
+
+### Diagnostic
+[Class documentation]
+
+### DiagnosticCollection
+[Interface documentation]
+
+### DiagnosticSeverity
+[Enum documentation]
+
+### DiagnosticRelatedInformation
+[Class documentation]
+
+### DiagnosticTag
+[Enum documentation]
+
+## Functions
+
+### createDiagnosticCollection()
+[Function documentation]
+
+### getDiagnostics()
+[Function documentation]
+
+## Events
+
+### onDidChangeDiagnostics
+[Event documentation]
+
+## Usage Examples
+
+### Basic Example
+[Code example with explanation]
+
+### Advanced Example
+[Code example with explanation]
+
+## Common Patterns
+[Patterns discovered from internal usage]
+
+## Error Handling
+[Error cases and handling strategies]
+```
+
+## Tips
+
+- Use the VS Code repository's TypeScript definitions (src/vs/vscode.d.ts) to find exact API signatures
+- Search for internal usage in src/vs/workbench/ and extensions/ directories to discover real-world patterns
+- Include behavioral notes that aren't obvious from type signatures (e.g., disposal requirements, threading considerations)
+- Document the relationship between DiagnosticCollection.set() and getDiagnostics()
+- Explain when onDidChangeDiagnostics fires and what information it provides
+
+## Evaluation
+
+Your documentation will be scored on:
+- **API completeness** (40%): Coverage of all required API methods, properties, and types
+- **Behavioral notes** (30%): Correct description of non-obvious behaviors, lifecycle, error cases
+- **Usage examples** (20%): Quality and correctness of code examples from internal callers
+- **Structure** (10%): Organization, clarity, and completeness of documentation structure

benchmarks/ccb_docgen/docgen-api-001/task.toml

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+[task]
+category = "api_reference"
+suite = "ccb_docgen"
+name = "docgen-api-001"
+language = "typescript"
+difficulty = "hard"
+time_limit_sec = 1200
+
+[task.metadata]
+description = "Generate API reference documentation for VS Code's Diagnostic API"
+tags = ["documentation", "api-reference", "vscode", "typescript"]