Session Context Builder

Session Context Builder

This skill extracts reusable context from prior Codex sessions and writes a compact context.md.

Use it when the user wants continuity across sessions without carrying forward the entire transcript.

Inputs

• one or more session IDs, or
• a time window such as last 1 day, last 7 days, last 30 days, last 90 days, last 365 days, or all time
• (optional) specific topic or scope to focus on within those sessions If the user does not specify an output path, default to context.md in the current directory.

Workflow

1. Read only the requested sessions from ~/.codex/sessions.
2. Extract the durable technical context:
   • problem statement
   • key decisions
   • recurrent flows, patterns, and issues.
   • important constraints
   • relevant paths, repos, or services
   • unfinished work
   • open questions
3. Remove chatter, repetition, and temporary dead ends unless they explain an important constraint.
4. Write a concise context.md that a fresh Codex run can consume quickly.

What To Preserve

• decisions that changed implementation direction
• terminology the project already uses
• boundaries the user explicitly cares about
• unresolved blockers
• assumptions that still need validation

What To Omit

• greetings and conversational filler
• repeated reasoning that did not change the outcome, or reasoning that is not relevant to the current context
• narrow command output unless it matters later
• implementation detail that is already captured more clearly elsewhere

Output Shape

Structure context.md around:

• current objective
• established facts
• key decisions
• recurrent flows, patterns, and issues
• relevant files and systems
• open questions
• next useful starting point

Guardrails

• Do not flatten uncertainty into false confidence.
• When prior sessions disagree, call that out explicitly.
• Prefer short durable statements over long chronology.