copilot-credit-usage

A Pi extension that monitors GitHub Copilot AI credit usage.

It provides:

• A footer/status-line indicator for Copilot usage in the current Pi session.
• A /copilot-credits command that shows Copilot usage grouped by local project, plus a total across all projects.
• Optional authoritative GitHub Billing API totals for the month.
• A copilot_credit_usage tool so the assistant can answer usage questions directly.

What it measures

GitHub documents Copilot usage as GitHub AI Credits, where 1 AI credit = $0.01 USD. This extension uses that conversion in two places:

1. Local Copilot session estimate: Pi stores provider, model, token, and cost metadata on assistant messages. The extension includes only messages whose provider, api, or model matches copilot|github-copilot. If Pi records a non-zero USD cost, the extension converts that cost to AI credits. If Pi records $0, the extension estimates cost from GitHub's published per-token Copilot model pricing and groups it by session/project.

2. GitHub Billing API total: When credentials are available, the extension calls GitHub's AI credit usage endpoint for the signed-in user:

   GET /users/{username}/settings/billing/ai_credit/usage?year=YYYY&month=M
   

The GitHub API total is account-level. It does not include your local Pi working directory, so per-project breakdown comes from Copilot-filtered local Pi sessions.

The local per-project report is still an estimate because GitHub's Billing API is account-level and does not expose local working directories. The GitHub Billing API section is the authoritative account total when available.

Install

From this directory:

pi install .

Or add this package to your Pi package list if you manage packages manually.

Usage

Footer/status line

After the extension loads, the bottom status area shows current Copilot session usage:

Copilot 12.3cr · 450.2ktok

If you set a plan or allowance, it also shows the monthly allowance:

export PI_COPILOT_PLAN=pro        # pro, pro+, max
# or
export PI_COPILOT_CREDIT_ALLOWANCE=1500

Status example:

Copilot 12.3cr/1,500cr · 450.2ktok

Monthly report command

/copilot-credits
/copilot-credits 2026-06
/copilot-credits --month 2026-06 --no-github
/copilot-credits --github-only --user monalisa
/copilot-credits --json

Options:

--month YYYY-MM     Month to report. Default: current month.
--local-only        Show local Copilot session estimate only.
--github-only       Show GitHub billing API total only.
--no-github         Skip GitHub billing API lookup.
--user LOGIN        GitHub username for billing endpoint.
--json              Emit JSON details.

GitHub API authentication

For official GitHub Billing API totals, use either:

export GITHUB_TOKEN=github_pat_...

or authenticate the GitHub CLI:

gh auth login

The token must be a fine-grained token with Plan: read user permission for user billing endpoints.

If credentials are missing or the account is not billed as an individual Copilot account, the extension still shows Copilot-filtered local Pi session estimates and prints the GitHub API error.

Notes and limits

• Local project totals are estimates based on Pi-recorded Copilot provider/model usage only.
• When Pi records $0 for a Copilot message, the extension estimates cost from GitHub's published per-token pricing for supported Copilot models.
• Override the local Copilot filter with PI_COPILOT_PROVIDER_PATTERN or COPILOT_PROVIDER_PATTERN if your provider name differs.
• GitHub Billing API totals are authoritative but account-level.
• Code completions and next-edit suggestions are not billed in Copilot AI credits for paid plans, per GitHub docs.
• Local monthly grouping uses calendar month (YYYY-MM). Your GitHub billing cycle may start on a different day.
• Project rows are capped at 100 to avoid huge command output.