Documentation Index
Fetch the complete documentation index at: https://docs.a21e.com/llms.txt
Use this file to discover all available pages before exploring further.
Credit model
a21e uses a simple credit system: 1 credit = 1 enhancement (one prompt compilation and execution).
Your balance is split into two buckets:
| Type | Source | Behavior |
|---|
| Subscription | Monthly plan | Resets on your renewal date |
| Add-on | Credit packs, admin grants | Never expires, never resets |
Credits are consumed subscription-first. Add-on credits are only used once subscription credits are exhausted.
Checking your balance
curl https://api.a21e.com/v1/credits/balance \
-H "Authorization: Bearer YOUR_API_KEY"
{
"balance": 550,
"plan": "pro",
"mode": "managed"
}
The balance field is your total available credits (subscription + add-on). mode indicates whether you’re on managed (a21e-hosted LLM) or BYOK (your own provider key).
Managed vs. BYOK
| Managed | BYOK |
|---|
| Credit cost | 1 credit per enhancement | 1 credit per enhancement |
| LLM cost | Included in credit | Billed by your provider |
| Setup | Nothing extra | Add provider key in settings |
Credits are always required — they cover prompt engineering, context assembly, and orchestration. In BYOK mode, your provider handles the LLM inference cost separately.
See BYOK guide for setup instructions.
Usage tracking
Summary
Get a high-level overview of your usage over a time period:
curl "https://api.a21e.com/v1/usage/summary?days=30" \
-H "Authorization: Bearer YOUR_API_KEY"
Daily breakdown
curl "https://api.a21e.com/v1/usage/by-day?days=30" \
-H "Authorization: Bearer YOUR_API_KEY"
Run history
List individual runs with pagination:
curl "https://api.a21e.com/v1/usage/runs?days=30&limit=20&offset=0" \
-H "Authorization: Bearer YOUR_API_KEY"
Each run includes the prompt title, credits used, model, provider, status, and duration.
CSV export
Export your run history as a CSV file for accounting or analysis:
curl "https://api.a21e.com/v1/usage/runs/export?days=30" \
-H "Authorization: Bearer YOUR_API_KEY" \
-o runs.csv
Credit ledger
The ledger provides a full audit trail of every credit transaction.
List transactions
curl "https://api.a21e.com/v1/credits/ledger?limit=50&offset=0" \
-H "Authorization: Bearer YOUR_API_KEY"
Each entry includes a entry_type field:
| Entry type | Meaning |
|---|
debit | Credit consumed by an enhancement |
refund | Credits returned (e.g. failed execution) |
grant | Credits added by admin or credit pack |
pinned_hit | Prompt pinning cache hit (no credit charged) |
dedup_hit | Deduplication cache hit (no credit charged) |
Period summary
Get aggregated credit activity over a time window (up to 90 days):
curl "https://api.a21e.com/v1/credits/ledger/summary?days=30" \
-H "Authorization: Bearer YOUR_API_KEY"
{
"total_debits": 142,
"total_refunds": 3,
"total_grants": 0,
"cache_hits": 28,
"net_change": -139,
"period_days": 30,
"since": "2026-02-06T00:00:00.000Z"
}
Insufficient credits
When your balance reaches zero, API requests return a 402 error:
{
"error": "INSUFFICIENT_CREDITS",
"message": "Your credit balance is 0. Purchase additional credits or upgrade your plan.",
"balance": 0
}
This applies to both managed and BYOK modes — credits are always required for prompt engineering.
Organization credits
Organizations have a separate credit pool shared across all members:
- Org admins can purchase credits and set per-member spending limits
- Member usage is tracked individually within the org pool
- When a member’s personal credits are exhausted, org credits are used (if allowed by policy)
See Organizations for more on team billing.