These docs describe the reference manufacturing API at sinter.systems. A sinter.ac subscription covers the project-planning workspace; manufacturing API access is separate.

API reference

Base URL: https://sinter.systems
Format: JSON; POST /v1/quotes is multipart/form-data.
Errors: Statuses and errors
Schema: /docs/openapi.json

Account

GET`/v1/me`

API key

The customer account and the key in use.

Returns · 200

`customer`	The account.
`key`	name, prefix, scopes of the key in use.
`auth`	How the call was authenticated.

Errors

401 Missing, wrong or revoked key.

POST`/v1/billing/portal`

Signed-in person only

A link to the card payment portal: saved cards and receipts.

API keys get 403.

Returns · 200

url The portal.

Errors

404 No billing account: the account hasn’t paid by card yet, or the portal isn’t set up.

Device login

POST`/v1/device/start`

Public

Starts a device login.

Body · `application/json` · optional

Name	Type	Notes
`name`	`string`	What the agent or script is; shown to the person approving. Default "Agent". ≤ 80 chars.
`scopes`	`array of quotes \| orders \| purchase`	quotes, orders, purchase. Default quotes and orders. purchase only if the person approving allows purchases. ≥ 1 item.

Returns · 200

`device_code`	Secret. Used to poll for the key.
`user_code`	The code the person approves.
`verification_url`	Where the person approves it.
`verification_url_complete`	The same page with the code filled in.
`expires_in`	Seconds until the codes expire (600).
`interval`	Seconds between polls.

Errors

429 Too many logins started.

POST`/v1/device/token`

Public

Returns the API key once the person has approved the device login.

Body · `application/json`

Name	Type	Notes
`device_code` required	`string`	≤ 200 chars.

Returns · 200

`api_key`	The key. Shown once.
`key`	name, prefix, scopes. scopes are what the person granted, which may be fewer than asked for.

Errors

`400 authorization_pending`	Not approved yet. Poll again after interval seconds.
`400 slow_down`	Polling too fast. Wait longer between polls.
`400 access_denied`	Denied. Final.
`400 expired_token`	Expired. Final.
`400 invalid_grant`	Unknown or already used code. Final.
`429`	Too many polls.

GET`/v1/device/{user_code}`

Signed-in person only

A pending device login, for the /device page.

API keys get 403.

Path

Name	Type	Notes
`user_code` required	`string`

Returns · 200

scopes_supported quotes, orders, purchase.

POST`/v1/device/{user_code}/approve`

Signed-in person only

Approves a device login.

API keys get 403.

Path

Name	Type	Notes
`user_code` required	`string`

Body · `application/json` · optional

Name	Type	Notes
`scopes`	`array of quotes \| orders \| purchase`	A subset of the scopes asked for. Left out: all of them. ≥ 1 item.

Returns · 200

Errors

409 Already approved or denied.

POST`/v1/device/{user_code}/deny`

Signed-in person only

Denies a device login.

API keys get 403.

Path

Name	Type	Notes
`user_code` required	`string`

Returns · 200

Errors

409 Already approved or denied.

Connected apps

GET`/v1/oauth/requests/{handle}`

Signed-in person only

A pending MCP connection request, for the /oauth/consent page.

API keys get 403.
The first account to open a request holds it.

Path

Name	Type	Notes
`handle` required	`string`

Returns · 200

`client`	id, name, claimed_uri (unverified), verified_domain (only for a client named by its metadata document URL).
`redirect_uri`	Where the browser returns after the decision.
`requested_scopes`	What the client asked for.
`scopes`	Requested; once approved, granted.
`status`	pending, approved or denied.
`expires_at`	Unix time. 10 minutes after the request.

Errors

`403`	Opened by another account.
`404`	Unknown or expired.

POST`/v1/oauth/requests/{handle}/approve`

Signed-in person only

Approves an MCP connection request.

API keys get 403.

Path

Name	Type	Notes
`handle` required	`string`

Body · `application/json` · optional

Name	Type	Notes
`scopes`	`array of quotes \| orders \| purchase`	A subset of the scopes asked for. Left out: the asked-for scopes other than purchase. ≥ 1 item.

Returns · 200

redirect_to The client’s redirect URI with the code.

Errors

`400`	Scope not asked for, or none approved.
`403`	Opened by another account.
`404`	Unknown or expired.
`409`	Already approved or denied.

POST`/v1/oauth/requests/{handle}/deny`

Signed-in person only

Denies an MCP connection request.

API keys get 403.

Path

Name	Type	Notes
`handle` required	`string`

Returns · 200

redirect_to The client’s redirect URI with error=access_denied.

Errors

`403`	Opened by another account.
`404`	Unknown or expired.
`409`	Already approved or denied.

GET`/v1/oauth/grants`

Signed-in person only

Connected apps: the account’s MCP connections.

API keys get 403.

Returns · 200

grants[] id, client_id, client_name, scopes, created_at, last_used_at, revoked_at.

DELETE`/v1/oauth/grants/{grant_id}`

Signed-in person only

Revokes an MCP connection and its tokens.

API keys get 403.

Path

Name	Type	Notes
`grant_id` required	`string`

Returns · 200

Errors

404 Unknown grant, or another account’s.

API keys

GET`/v1/keys`

Signed-in person only

The account’s API keys.

API keys get 403.

Returns · 200

`keys[]`	name, prefix, scopes. Never the secret.
`scopes_supported`	quotes, orders, purchase.

POST`/v1/keys`

Signed-in person only

Creates an API key. The secret is in this response only.

API keys get 403.

Body · `application/json` · optional

Name	Type	Notes
`name`	`string`	Default "API key". ≤ 80 chars.
`scopes`	`array of quotes \| orders \| purchase`	quotes, orders, purchase. Default quotes and orders. purchase is Allow purchases. ≥ 1 item.

Returns · 201

DELETE`/v1/keys/{key_id}`

Signed-in person only

Revokes an API key.

API keys get 403.

Path

Name	Type	Notes
`key_id` required	`string`

Returns · 200

Materials

GET`/v1/materials`

Public

Materials, colors, print settings and lead times.

Returns · 200

`materials[].id`	PLA+, PLA-CF, PETG, PETG-CF, ASA, ASA-CF, PC, PC-CF, TPU, TPU-CF, Nylon, Nylon-CF, PPA-CF, PPS-CF, Custom.
`materials[].available`	false: out of stock; new quotes in it are refused.
`materials[].lead_days`	The material’s lead days in the default color (the first of colors), already included in a quote’s ship_by. PLA+ and PETG in black or white ship without material lead time; other materials and colours add one day.
`materials[].same_day_colors`	The colors the material ships in without lead days; empty when every color adds one. A color change re-dates a quote.
`materials[].custom`	true: any other material, named in material_note.
`speeds[]`	speed, label, days and optional asap_offset_days of each lead time. Economy uses speed week, days null and asap_offset_days 7.
`colors`	Filament colors; the first is the default.
`custom_color`	The color to send with color_note for any other color (Custom); Sinter reviews it. null when not offered.
`print_settings[]`	Settings a quote may change: name, label, type (float, int, choice or face), min and max or choices, unit; automatic: true when Sinter chooses it for the part if left out; range_by and ranges when the range follows another setting. Left out, a setting is Standard (or Automatic). The ranges are the printers’ own; see Materials.

Quotes

POST`/v1/quotes`

Scope: quotes

Uploads a model and starts a quote.

Returns status received, or quoted at once. Until quoted, needs_review, engineering or failed, poll GET /v1/quotes/{quote_id} every 5 to 10 seconds.
Quoted prices are binding.

Headers

Name	Type	Notes
`Idempotency-Key`	`string`	Any unique string up to 200 characters. A retried upload returns the same quote.

Body · `multipart/form-data`

Name	Type	Notes
`file` required	`file`	STEP, STL, OBJ or 3MF, up to 50 MB.
`material`	`PLA+ \| PLA-CF \| PETG \| PETG-CF \| ASA \| ASA-CF \| PC \| PC-CF \| TPU \| TPU-CF \| Nylon \| Nylon-CF \| PPA-CF \| PPS-CF \| Custom`	Default "PLA+".
`material_note`	`string`	Required for Custom: the material wanted. ≤ 320 chars.
`quantity`	`integer`	Default 1. 1–100.
`units`	`mm \| cm \| in`	What an STL or OBJ was drawn in. Ignored for STEP and 3MF. Default "mm".
`color`	`string`	One of the colors in /v1/materials. ≤ 40 chars.
`color_note`	`string`	Required for the Custom color: the color wanted. Sinter reviews the quote. ≤ 320 chars.

Returns · 202

Errors

`400`	Refused, for example a material out of stock. See detail.
`413`	File too large.
`415`	Unsupported file type.
`422`	Invalid input.
`429`	A limit was reached. Wait Retry-After seconds.

GET`/v1/quotes`

Scope: quotes

The account’s quotes, newest first.

limit: 1–100 (default 50). Pass next_cursor as cursor to read the next page; null means the last page.

Path

Name	Type	Notes
`limit`	`integer`	1–100.
`cursor`	`string`	≤ 64 chars.

Returns · 200

GET`/v1/quotes/{quote_id}`

Scope: quotes

One quote.

Path

Name	Type	Notes
`quote_id` required	`string`

Returns · 200

`status`	See Statuses and errors.
`options[]`	One per lead time: speed, label, days, ship_by, total_cents, unit_cents, available, note. days is null for current options: use ship_by as the Pacific calendar day it falls on. Economy has asap_offset_days: 7, relative to the Default ship date; material lead time is already included.
`tier`	instant, assisted or engineered.
`file_id`	The file the quote was made from: the same for every quote of the same file (its requotes, or the file uploaded again under any name), different for another file even under the same name. Not comparable across accounts.
`part`	dimensions_mm: the part’s size as uploaded, in its own axes.
`ship_date_pending`	true until Sinter confirms the ship date of an assisted quote. ship_by is null until then.
`estimate_cents`	Status engineering only: an estimate. options is empty.
`estimate_pending`	Status engineering only: true while estimate_cents updates after a change.
`request_status`	Engineering review requests: draft (not sent; editable with requote), open (sent; editable with requote), accepted or rejected. null otherwise.
`units`	mm, cm or in for STL and OBJ; null for STEP and 3MF.
`print_settings`	Changes from Standard, by name. {} for none.
`manufacturability`	Structured analysis: analysis_id, version, status, checked, not_assessed, review_required, review_completed and findings. Read again after changes; screened is not a full DFM certification.
`flags`	Manufacturability findings: code, level (block or warning), message and features. Warnings can appear on quoted parts. Read alongside status and tier; an empty array is not a guarantee of suitability.
`progress`	While received or processing: stage (queued, checking, processing), fraction (0 to 1), ahead (quotes queued before this one).
`review_url`	The quote page, with a 3D preview. Anyone with the link can see it; only the account that owns the quote, signed in, can change, pay for or cancel it there.
`delivery`	method (courier or shipping), city, fee_cents and, for shipping, transit_days, once delivery is priced.
`delivery_required`	true: accept needs a delivery price.

Errors

404 Not found, or another account’s quote.

POST`/v1/quotes/{quote_id}/requote`

Scope: quotes

Changes material, quantity, units, color or print settings before payment.

Status received or processing: changed in place, same id. A quantity, color or Custom material name change keeps the work under way; a material, units or print_settings change starts it again.
Status engineering with request_status draft or open: changed in place, same id, still an engineering request. A material or print_settings change updates estimate_cents; estimate_pending is true until then. A change that no longer needs review, or a units change, returns a new quote and replaces this one.
request_status accepted or rejected: a new request with its own id. The accepted quote stays payable as issued.
Any other status: a new quote with its own id. An issued engineered quote stays payable as issued.
Use the id returned. Returns status quoted, received or engineering; poll.
Also refreshes an expired quote. There is no daily quote-count limit.

Path

Name	Type	Notes
`quote_id` required	`string`

Body · `application/json`

Name	Type	Notes
`material`	`PLA+ \| PLA-CF \| PETG \| PETG-CF \| ASA \| ASA-CF \| PC \| PC-CF \| TPU \| TPU-CF \| Nylon \| Nylon-CF \| PPA-CF \| PPS-CF \| Custom`
`material_note`	`string`	Custom only. Kept when left out. ≤ 320 chars.
`quantity`	`integer`	1–100.
`units`	`mm \| cm \| in`	Unchanged when left out.
`color`	`string`	Unchanged when left out. ≤ 40 chars.
`color_note`	`string`	Custom color only. Kept when left out. ≤ 320 chars.
`print_settings`	`object`	Settings by name from /v1/materials print_settings, within their ranges. {} resets them to Standard (or Automatic). Unchanged when left out.

Returns · 201

Errors

`400`	Refused, for example a setting out of range. See detail.
`409`	Paid, or the file is no longer stored.
`429`	A limit was reached. Wait Retry-After seconds.

POST`/v1/quotes/{quote_id}/claim`

Scope: quotes

Moves a quote made without an account to this account.

The quote gets a new review_url. The old link stops working.

Path

Name	Type	Notes
`quote_id` required	`string`

Body · `application/json`

Name	Type	Notes
`token` required	`string`	The last part of the guest quote’s review_url. ≤ 200 chars.

Returns · 200

Errors

`404`	Token doesn’t match.
`409`	Another account has the quote, or a card payment is in progress.

POST`/v1/quotes/{quote_id}/request`

Scope: quotes

Sends a draft engineering request (request_status draft) to Sinter’s engineers.

Nothing is reviewed until it is sent. Send only when the user asks; let them change it with requote first.
Returns the quote with request_status open. Sending one already sent returns it unchanged.
An unsent draft expires a day after pricing. A sent request expires 14 days after sending unless issued.

Path

Name	Type	Notes
`quote_id` required	`string`

Returns · 200

Errors

409 Not status engineering, or the draft expired. Requote it.

POST`/v1/quotes/{quote_id}/cancel`

Scope: quotes

Withdraws a quote in status engineering.

Path

Name	Type	Notes
`quote_id` required	`string`

Returns · 200

Errors

409 Any other status. Not withdrawn.

POST`/v1/quotes/{quote_id}/delivery`

Scope: quotes

Prices delivery to an address: local courier, or carrier shipping if the user chooses it.

Local courier inside the San Francisco Bay Area delivery area.
Outside it, or when the courier can’t take the address: 422 carrier_shipping_available. Ask the user. Only if they choose carrier shipping, send the address again with accept_carrier true.
The quote’s delivery then shows method, city, fee_cents and, for shipping, transit_days. The address is not returned.
The fee is charged at checkout as its own line, and doesn’t change after payment.
Every quote needs a delivery price before it can be paid. A courier price is good for 24 hours.

Path

Name	Type	Notes
`quote_id` required	`string`

Body · `application/json`

Name	Type	Notes
`name` required	`string`	≤ 80 chars.
`phone` required	`string`	≤ 30 chars.
`street` required	`string`	≤ 120 chars.
`unit`	`string`	≤ 60 chars.
`city` required	`string`	≤ 80 chars.
`state` required	`string`	Two letters. /^[A-Za-z]{2}$/.
`zip` required	`string`	/^\d{5}(-\d{4})?$/.
`country`	`"US"`	Default "US".
`notes`	`string`	For the courier. ≤ 280 chars.
`accept_carrier`	`boolean`	true only after the user chooses carrier shipping. Default false.

Returns · 200

Errors

`422 carrier_shipping_available`	Outside the courier area. Ask the user, then send again with accept_carrier true.
`422 couriers_unavailable`	No courier right now. Try again later.
`422 outside_delivery_area`	No delivery to that address.
`422 outside_shipping_area`	No carrier shipping to that address.
`422 shipping_review_required`	Held for review by Sinter.
`422 delivery_invalid`	Check the address and phone.
`502`	Courier service error. Retry.
`503`	Delivery is not available.

POST`/v1/quotes/{quote_id}/accept`

Scope: purchase

Accepts a quote at one lead time. This is a purchase.

Only with Allow purchases on for the key or agent, and the user’s approval of this purchase. See Rules for agents.
Pick an option whose available is true.
Every order is paid by card first: 402 payment_required with checkout_url. A person pays there; the quote becomes accepted once payment completes.
A quote already paid: 200 and the order.
Needs a delivery price: send delivery here, or call POST /v1/quotes/{quote_id}/delivery first.

Path

Name	Type	Notes
`quote_id` required	`string`

Headers

Name	Type	Notes
`Idempotency-Key`	`string`	Required. The same key with the same request returns the first answer for 24 hours. A repeated 402 with an expired checkout link returns a new link.

Body · `application/json` · optional

Name	Type	Notes
`speed`	`asap \| week`	asap (Default) or week (Economy). Historical speed names are not accepted for new purchases. Default "week".
`delivery`	`object`	Prices delivery in the same call; same fields as POST /v1/quotes/{quote_id}/delivery.
`name` required	`string`	≤ 80 chars.
`phone` required	`string`	≤ 30 chars.
`street` required	`string`	≤ 120 chars.
`unit`	`string`	≤ 60 chars.
`city` required	`string`	≤ 80 chars.
`state` required	`string`	/^[A-Za-z]{2}$/.
`zip` required	`string`	/^\d{5}(-\d{4})?$/.
`country`	`"US"`	Default "US".
`notes`	`string`	≤ 280 chars.
`accept_carrier`	`boolean`	Default false.

Returns · 200

Errors

`402 payment_required`	checkout_url: give it to the user.
`403`	The key lacks the purchase scope.
`409`	Expired, held for review, status engineering, the option is no longer available, or delivery not priced.
`409 ship_date_changed`	The Default ship date moved to a later day; ship_by has the new one. Accept again only if the user agrees.
`422 carrier_shipping_available`	As for POST /v1/quotes/{quote_id}/delivery.
`428`	No Idempotency-Key.

Orders

GET`/v1/orders`

Scope: orders

The account’s accepted orders, newest first.

limit: 1–100 (default 50). Pass next_cursor as cursor to read the next page; null means the last page.

Path

Name	Type	Notes
`limit`	`integer`	1–100.
`cursor`	`string`	≤ 64 chars.

Returns · 200

GET`/v1/orders/{order_id}`

Scope: orders

One order. The order id is the quote id.

Shipped more than one full business day (Monday to Friday, Pacific) after its ship-by date: 10% of parts plus corresponding tax is refunded. Delivery charges are excluded.

Path

Name	Type	Notes
`order_id` required	`string`

Returns · 200

`status`	queued, in_production, on_hold, completed, cancelled.
`parts[]`	unit, status and progress (0 to 1).
`ship_by`	Promised ship date. null while ship_date_pending is true.
`paid`	true once paid by card.
`tracking`	Set once the order ships.
`delivery`	method, city, fee_cents; transit_days and arrives_by for shipping; once packed, state, eta, delivered_at, carrier, tracking_number, tracking_url.

POST`/v1/orders/{order_id}/cancel`

Scope: orders

Paid orders are committed and can't be cancelled; unpaid quotes are cancelled from the quote link.

No refund once paid. If Sinter can't fulfill or declines an order, everything paid is refunded to the card, delivery and tax included.
No partial cancellation.

Path

Name	Type	Notes
`order_id` required	`string`

Returns · 200

Errors

409 Paid orders can't be cancelled. Contact [email protected].

API reference

Account

GET/v1/me

Returns · 200

Errors

POST/v1/billing/portal

Returns · 200

Errors

Device login

POST/v1/device/start

Body · application/json · optional

Returns · 200

Errors

POST/v1/device/token

Body · application/json

Returns · 200

Errors

GET/v1/device/{user_code}

Path

Returns · 200

POST/v1/device/{user_code}/approve

Path

Body · application/json · optional

Returns · 200

Errors

POST/v1/device/{user_code}/deny

Path

Returns · 200

Errors

Connected apps

GET/v1/oauth/requests/{handle}

Path

Returns · 200

Errors

POST/v1/oauth/requests/{handle}/approve

Path

Body · application/json · optional

Returns · 200

Errors

POST/v1/oauth/requests/{handle}/deny

Path

Returns · 200

Errors

GET/v1/oauth/grants

Returns · 200

DELETE/v1/oauth/grants/{grant_id}

Path

Returns · 200

Errors

API keys

GET/v1/keys

Returns · 200

POST/v1/keys

Body · application/json · optional

Returns · 201

DELETE/v1/keys/{key_id}

Path

Returns · 200

Materials

GET/v1/materials

Returns · 200

Quotes

POST/v1/quotes

Headers

Body · multipart/form-data

Returns · 202

Errors

GET/v1/quotes

Path

Returns · 200

GET/v1/quotes/{quote_id}

Path

Returns · 200

Errors

POST/v1/quotes/{quote_id}/requote

Path

Body · application/json

Returns · 201

Errors

POST/v1/quotes/{quote_id}/claim

GET`/v1/me`

POST`/v1/billing/portal`

POST`/v1/device/start`

Body · `application/json` · optional

POST`/v1/device/token`

Body · `application/json`

GET`/v1/device/{user_code}`

POST`/v1/device/{user_code}/approve`

Body · `application/json` · optional

POST`/v1/device/{user_code}/deny`

GET`/v1/oauth/requests/{handle}`

POST`/v1/oauth/requests/{handle}/approve`

Body · `application/json` · optional

POST`/v1/oauth/requests/{handle}/deny`

GET`/v1/oauth/grants`

DELETE`/v1/oauth/grants/{grant_id}`

GET`/v1/keys`

POST`/v1/keys`

Body · `application/json` · optional

DELETE`/v1/keys/{key_id}`

GET`/v1/materials`

POST`/v1/quotes`

Body · `multipart/form-data`

GET`/v1/quotes`

GET`/v1/quotes/{quote_id}`

POST`/v1/quotes/{quote_id}/requote`

Body · `application/json`

POST`/v1/quotes/{quote_id}/claim`

Body · `application/json`

POST`/v1/quotes/{quote_id}/request`

POST`/v1/quotes/{quote_id}/cancel`

POST`/v1/quotes/{quote_id}/delivery`

Body · `application/json`

POST`/v1/quotes/{quote_id}/accept`

Body · `application/json` · optional

GET`/v1/orders`

GET`/v1/orders/{order_id}`

POST`/v1/orders/{order_id}/cancel`