Billing

Pricing shape ruled D173 (2026-08-19), amended D174 (2026-08-20) — retires the Spark/Sprint/Mission/Deploy pack model in favor of rolling-30-day free floors plus per-action credit pricing and a volume-discount slider. GET /v1/capabilities is authoritative for numeric rates and tier copy.

Check status

GET /v1/billing
Authorization: Bearer ltx_your_key

Returns a snapshot of the authenticated agent:

Field	Meaning
`tier`	DB tier column (`spark`, legacy pack names, or `starter`/`pro` for older subscriptions)
`credits_remaining_usd`	Current spendable credit balance (USD string, 4 decimal places)
`credits_expire_at`	Legacy pack expiry for historical rows; purchased slider credits do not expire (D174)
`tier_label`	Human-readable tier name
`auto_topup`	`true` if auto top-up is configured
`over_limit`	`true` if storage, memory, or parse quota is at cap
`memory_ops_this_month`	Memory operations logged this UTC month
`memory_storage_bytes`	KV JSON storage (bytes)
`blob_embed_storage_bytes`	Bytes used by parsed document chunk embeddings
`combined_memory_storage_bytes`	`memory_storage_bytes + blob_embed_storage_bytes`
`search_calls_this_month`	Web-discovery calls this UTC month
`browse_calls_this_month`	Browse calls this UTC month
`parse_ops_this_month` / `parse_ops_lifetime`	Parse usage

Free floors (D173/D174)

Before any credit is charged:

Action	Free floor	Window
Memory write	1,000	Rolling 30 days
Search	50	Rolling 30 days
Browse	20	Rolling 30 days

Past the floor: memory write 1 credit ( $0.01)**, search **2 credits ($ 0.02), browse static 3 credits ( $0.03)** / **dynamic 5 credits ($ 0.05). See Pricing for the volume-discount slider rates.

Buy credits (slider)

POST /v1/billing/credits/checkout
Authorization: Bearer ltx_your_key
Content-Type: application/json

{
  "credits": 2500
}

Returns honest unit_rate_usd and total_usd at the D173 volume-discount table. Until business registration completes (D125) and STRIPE_SLIDER_CHECKOUT_ENABLED is set, expect 503 with status: not_live and error_code: STRIPE_GATED_D125 — no Stripe Checkout Session is created.

Credits	Rate	Discount
1–999	$0.01/credit	base
1,000–4,999	$0.009/credit	10%
5,000–19,999	$0.0075/credit	25%
20,000+	$0.006/credit	40%

Purchased credit never expires (D174). Retired fixed packs used 180-day expiry on grant-only rows; slider purchases do not set expires_at.

Retired pack checkout

POST /v1/billing/packs/checkout returns 410 Gone (PACK_CHECKOUT_RETIRED). Fixed packs are historical only — use the slider endpoint above.

Auto top-up

Set a threshold and saved payment method — Lithtrix refills automatically when your balance drops below it.

POST /v1/billing/auto-topup
Authorization: Bearer ltx_your_key
Content-Type: application/json

{
  "enabled": true,
  "threshold_usd": "5.00",
  "pack": "sprint",
  "payment_method_id": "pm_..."
}

The pack field still reflects the pre-D173 auto-topup shape — slider migration is a follow-up when D125 unblocks charging.

Webhook

POST /v1/billing/webhook — Stripe-signed events. Configure STRIPE_WEBHOOK_SECRET on the host. Slider purchases use metadata purchase_type=slider when live.

Environment (ops)

STRIPE_SLIDER_CHECKOUT_ENABLED — false until D125 go-live (default)
STRIPE_SECRET_KEY, STRIPE_PUBLISHABLE_KEY, STRIPE_WEBHOOK_SECRET
Legacy pack Price IDs (STRIPE_PRICE_PACK_*) — dormant; retained for historical webhook rows only

See also GET /v1/capabilities for the pricing block and per-call rates, and Pricing for the full D173/D174 shape.

Getting Started

API Reference

Concepts

Integrations

Check status

Free floors (D173/D174)

Buy credits (slider)

Retired pack checkout

Auto top-up

Webhook

Environment (ops)

​Check status

​Free floors (D173/D174)

​Buy credits (slider)

​Retired pack checkout

​Auto top-up

​Webhook

​Environment (ops)

Check status

Free floors (D173/D174)

Buy credits (slider)

Retired pack checkout

Auto top-up

Webhook

Environment (ops)