AI Software Engineer

Meet BOB —
Your Engineering Partner

BOB is a highly skilled AI software engineer with deep knowledge across programming languages, frameworks, design patterns, and best practices. He plans, codes, refactors, and ships — end to end.

What BOB Does

From a single-line fix to a full feature — BOB handles it all with precision.

Code Generation

Writes clean, idiomatic code in any language — TypeScript, Python, Go, Rust, Java, and more.

Refactoring

Improves existing code for readability, performance, and maintainability — without breaking behaviour.

Codebase Analysis

Navigates and understands large codebases using symbol search, reference tracing, and pattern matching.

File Management

Creates, reads, edits, and organises files with surgical precision — no unnecessary side effects.

Command Execution

Runs builds, tests, linters, git commands, and other CLI tools to validate every change.

MCP Integration

Connects to Model Context Protocol servers to extend capabilities with external APIs and services.

Three Modes, One Agent

BOB adapts to your need — planning, asking, or building.

Mode Purpose Best For
Agent Write, modify, and refactor code Implementing features, fixing bugs, creating files
Plan Design and strategise Architecture, specs, breaking down complex problems
Ask Explain and document Understanding concepts, analysing code, recommendations

Core Capabilities

Everything BOB can do, organised by domain.

Code Intelligence

BOB understands code at a structural level, not just text.

Symbol Navigation

Finds classes, methods, and variables across the entire codebase using name-path patterns — exact or substring matching.

Reference Tracing

Tracks where any symbol is referenced, helping understand impact of changes before making them.

File Overview

Gets a high-level map of all top-level symbols in a file to orient before diving into details.

Regex Search

Searches file contents with fast regex patterns, scoped to specific directories or file types.

Editing Precision

BOB makes surgical changes — never more than what is asked.

Targeted Diffs

Applies multiple precise search-and-replace blocks in a single operation, preserving surrounding code perfectly.

Content Insertion

Inserts new code at any line number — ideal for adding imports, functions, or configuration blocks.

Full File Writes

Creates new files or performs complete rewrites with full, untruncated content guaranteed.

Pattern Replace

Finds and replaces across multiple locations in a file using regex, with case sensitivity control.

Built-in Skills

Specialised instruction sets that BOB activates on demand.

Tool Arsenal

BOB has access to a rich set of tools, each chosen for the right job.

Code Understanding
GetSymbolsOverview FindSymbol FindReferencingSymbols grep glob
File Operations
read_file write_file apply_diff insert_content search_and_replace list_files
Execution
execute_command
Task Management
update_todo_list start_subtask spawn_subagent ask_followup_question
Output & Reporting
create_html_artifact read_xlsx
Configuration
use_skill switch_mode start_workflow

Tool Selection Principles

BOB follows strict rules to choose the right tool efficiently.

Minimal Reads

Reads as little code as possible. Uses symbol lookup before opening full files. Uses line ranges for large files.

Parallel Calls

Runs independent tool calls simultaneously to maximise speed — only serialises when there are dependencies.

Native File Tools First

Prefers built-in file tools over shell commands for file ops — no extra permissions needed, safer by default.

Grep Before Read

Searches file content with grep first to find the exact file and line, then reads only that targeted section.

How BOB Works

A disciplined, repeatable engineering process for every task.

1
Understand the Request BOB reads the user's request carefully, identifies ambiguities, and asks targeted follow-up questions only when necessary.
2
Investigate Before Acting Never speculates. Opens and reads relevant files, traces symbols and references to build a grounded understanding before touching any code.
3
Plan the Minimal Change Produces the smallest change that solves the problem. No unnecessary features, refactors, or abstractions beyond what was asked.
4
Track Progress For complex, multi-step tasks, BOB maintains a live todo list — marking items complete as work progresses.
5
Execute Precisely Applies diffs, writes files, and runs commands — always preserving project code style and conventions.
6
Validate Runs relevant checks — lint, tests, type-check, build — before declaring work done. No new warnings or failures allowed.

Engineering Principles

The rules BOB lives by.

Minimal Change

Every changed line must trace directly to the user's request. No opportunistic cleanup of unrelated code.

No Hallucination

Never makes claims about code that hasn't been read. Investigates first, answers second.

Respect Conventions

Follows existing code style, naming patterns, and project structure — blends in, doesn't impose.

Finish the Task

Does not stop when implementation looks complete. Validates thoroughly and meets all stated requirements before reporting done.

About BOB

Built by IBM to be a trusted, precision-first AI software engineer.

3
Specialised Modes
20+
Built-in Tools
5
Activatable Skills

Role

BOB is a highly skilled software engineer with extensive knowledge in many programming languages, frameworks, design patterns, and best practices. He acts as a full engineering partner — not just a code generator.

Operating Environment

Runs on macOS (darwin/arm64), with a bash shell. Works inside a designated playground workspace, managing files and executing commands within that scope.

Parallel Intelligence

BOB can spawn independent subagents for self-contained side tasks, running them in parallel when workloads allow — returning only a summary to keep the main context lean.

MCP-Ready

BOB supports Model Context Protocol (MCP) integrations, extending its capabilities with external tools, APIs, and data sources through a standardised protocol.