@calesennett/pi-codex-fast

pi extension that adds Fast and Ultrafast service tiers to supported OpenAI requests.

Packages

Package details

extension

Install @calesennett/pi-codex-fast from npm and Pi will load the resources declared by the package manifest.

npm report
$ pi install npm:@calesennett/pi-codex-fast
Package
@calesennett/pi-codex-fast
Version
0.1.7
Published
Sep 5, 2026
Downloads
813/mo · 166/wk
Author
calesennett
License
unknown
Types
extension
Size
245.5 KB
Dependencies
0 dependencies · 1 peer

Security note

Pi packages can execute code and influence agent behavior. Review the source before installing third-party packages.

README

pi-codex-fast

This pi extension adds Fast and Ultrafast service tiers to supported OpenAI requests.

Usage

Inside pi:

  • /codex-fast toggles Fast mode.
  • /codex-ultrafast toggles Ultrafast mode.

From CLI:

  • pi --fast
  • pi --ultrafast

You cannot enable both modes at the same time.

Persistence

The extension reads the mode from these pi settings files:

  • global: $PI_CODING_AGENT_DIR/settings.json (or ~/.pi/agent/settings.json)
  • project override: <cwd>/.pi/settings.json

Use the key pi-codex-fast.mode. The allowed values are off, fast, and ultrafast. The extension also accepts the old enabled key.

Writes go to the global settings file.

Behavior

Fast mode sets service_tier: "priority" for these models:

  • openai-codex/gpt-5.4
  • openai-codex/gpt-5.5
  • openai-codex/gpt-5.6-sol
  • openai-codex/gpt-5.6-terra
  • openai-codex/gpt-5.6-luna
  • openai-codex/gpt-6-astra

Ultrafast mode sets service_tier: "ultrafast" for openai/gpt-5.6-sol. Your OpenAI API project must have Ultrafast access.

The extension does not change other requests.

Example benchmark

A local live benchmark is available in this repository under evals/. Three paired trials per model produced:

Model TTFB speedup Turn speedup Wall speedup
gpt-5.6-sol 1.52x 1.58x 1.57x
gpt-5.6-terra 1.05x 1.34x 1.33x
gpt-5.6-luna 1.30x 2.31x 2.25x