Why Was This Written? — VS Code Extension

Traces any line of code back through git blame → PR → ticket → LLM to explain why it was written, not just what it does.

Install

Search "Why Was This Written" in the VS Code Extensions panel (Ctrl+Shift+X), or install from the Marketplace.

Usage

Open any file in a git-tracked project
Click on the line you want to understand
Right-click → Why Was This Written?

A side panel will show:

An AI-generated explanation of why the code was introduced
The commit that introduced it
The pull request that merged it
Any linked Jira / Linear / GitHub issue tickets

Configuration

Open VS Code settings (Ctrl+,) and search "Why Was This Written":

Setting	Description
`githubToken`	GitHub PAT with `repo` scope — needed to look up pull requests
`llmProvider`	`openai` (default), `anthropic`, `ollama`, or `watsonx`
`openaiApiKey`	OpenAI API key (for GPT-4o)
`anthropicApiKey`	Anthropic API key (for Claude 3.5 Sonnet)
`ollamaBaseUrl`	Ollama server URL (default: `http://localhost:11434`)
`ollamaModel`	Ollama model name (default: `llama3`)
`watsonxApiKey`	IBM Cloud API key
`watsonxProjectId`	watsonx.ai project ID
`watsonxRegion`	watsonx.ai region (default: `us-south`)
`watsonxModel`	watsonx.ai model ID (default: `ibm/granite-13b-chat-v2`)
`jiraBaseUrl`	e.g. `https://yourorg.atlassian.net`
`jiraEmail`	Jira account email
`jiraApiToken`	Jira API token (from id.atlassian.com)
`linearApiKey`	Linear API key

The only required setting is githubToken + one LLM API key. Jira/Linear are optional — the extension works without them and will show commit + PR context only.

How it works

git blame → commit SHA
         → GitHub API → PR title + description + linked ticket IDs
                          → Jira / Linear / GitHub Issues (optional)
→ LLM (GPT-4o / Claude / Ollama / watsonx) → plain-English explanation
→ VS Code side panel

Ticket IDs are detected automatically from PR descriptions — e.g. Fixes KAN-42, Closes [#123](https://github.com/sureshk2a/why-does-this-exist/issues/123).

Source

github.com/sureshk2a/why-does-this-exist

Why Was This Written