Responses API

The LLM models speak the OpenAI Responses API at POST https://api.abstract.inc/v1/responses. They do not answer on /v1/chat/completions. That route serves the robot models.

Model id	Contract	`stream: true`
`glm-5.3:async`	Runs in the background. Poll for the result.	Buffered
`deepseek-v4-flash:async`	Runs in the background. Poll for the result.	Buffered
`glm-5.3:superfast`	Completes inline.	Live
`deepseek-v4-flash:superfast`	Completes inline.	Live
`kimi-k3:superfast`	Completes inline.	Live

GET /v1/models lists these ids. Use an id exactly as written. An id is a contract.

Request

curl -s https://api.abstract.inc/v1/responses \
  -H "Authorization: Bearer $(abstract token)" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: $(uuidgen)" \
  -d '{"model":"glm-5.3:async","input":"Summarise RFC 8628 in three sentences."}'

string

required

One of the ids above.

string | array

The OpenAI Responses input.

boolean

true returns server-sent events. Live on :superfast, buffered on :async.

integer

A positive integer, at most 65,536. Default 8,192 on glm-5.3:superfast and 4,096 on the others.

string

Not supported on any model.

boolean

true is not supported on a :superfast model.

boolean

true is not supported on a :superfast model.

The API refuses an unsupported field with HTTP 422 invalid_request before it reserves any cost. The request body is at most 2 MiB.

:async models

An :async model answers at once with a response whose status is queued or in_progress. Save its id. Poll GET /v1/responses/{id} until status is completed, failed, cancelled or incomplete. The job goes on when you disconnect. Use these models for long work nobody waits on.

curl -s https://api.abstract.inc/v1/responses/resp_abc123 \
  -H "Authorization: Bearer $(abstract token)"

Only the account that created a response can read it. Any other account gets HTTP 404 not_found.

Buffered streaming

"stream": true on an :async model returns a buffered stream:

response.created, then response.queued or response.in_progress.
: keepalive comments while the job runs.
The whole output as Responses events after the job finishes, then the terminal event and data: [DONE].

The answer carries X-Abstract-Streaming: buffered and a Location header with the response’s path. Buffered streaming does not shorten the time to the first token. A connection lasts at most 30 minutes, then ends with an error event whose code is stream_timeout. Closing the connection cancels nothing. Get the result with GET /v1/responses/{id}, or repeat the same POST with the same Idempotency-Key.

:superfast models

A :superfast model completes the response inline. Set "stream": true for live server-sent events when a person is waiting.

Idempotency-Key

Idempotency-Key is an optional header of 1 to 200 characters from A-Z a-z 0-9 _ . / : -.

The same POST with the same key returns the same response and never starts a second job.
The same key with a different body returns HTTP 409 idempotency_conflict.
Use a new key for a new request.
An accepted POST answers with an Idempotency-Key header. The API generates one when you send none.

Send a key whenever a client can retry, so a retry never starts a second job.

OpenAI SDK

Set the base URL to https://api.abstract.inc/v1 and read the key from ABSTRACT_API_KEY.

import os
import time
import uuid

from openai import OpenAI

client = OpenAI(base_url="https://api.abstract.inc/v1", api_key=os.environ["ABSTRACT_API_KEY"])

response = client.responses.create(
    model="glm-5.3:async",
    input="Summarise RFC 8628 in three sentences.",
    extra_headers={"Idempotency-Key": str(uuid.uuid4())},
)
while response.status in ("queued", "in_progress"):
    time.sleep(10)
    response = client.responses.retrieve(response.id)
print(response.status)
print(response.output_text)

import OpenAI from "openai"

const client = new OpenAI({
  baseURL: "https://api.abstract.inc/v1",
  apiKey: process.env.ABSTRACT_API_KEY,
})

let response = await client.responses.create(
  { model: "glm-5.3:async", input: "Summarise RFC 8628 in three sentences." },
  { headers: { "Idempotency-Key": crypto.randomUUID() } },
)
while (response.status === "queued" || response.status === "in_progress") {
  await new Promise((resolve) => setTimeout(resolve, 10_000))
  response = await client.responses.retrieve(response.id)
}
console.log(response.status)
console.log(response.output_text)

import os
import uuid

from openai import OpenAI

client = OpenAI(base_url="https://api.abstract.inc/v1", api_key=os.environ["ABSTRACT_API_KEY"])

stream = client.responses.create(
    model="kimi-k3:superfast",
    input="Write a haiku about a robot arm.",
    stream=True,
    extra_headers={"Idempotency-Key": str(uuid.uuid4())},
)
for event in stream:
    if event.type == "response.output_text.delta":
        print(event.delta, end="", flush=True)
print()

import OpenAI from "openai"

const client = new OpenAI({
  baseURL: "https://api.abstract.inc/v1",
  apiKey: process.env.ABSTRACT_API_KEY,
})

const stream = await client.responses.create(
  { model: "kimi-k3:superfast", input: "Write a haiku about a robot arm.", stream: true },
  { headers: { "Idempotency-Key": crypto.randomUUID() } },
)
for await (const event of stream) {
  if (event.type === "response.output_text.delta") process.stdout.write(event.delta)
}
process.stdout.write("\n")

Run a program with the key in its environment only, for example ABSTRACT_API_KEY="$(abstract token)" python async_poll.py.

Usage

A finished response carries usage with input_tokens, input_tokens_details.cached_tokens and output_tokens. The response is billed from those counts at the model’s per-million-token rates for input, cached input and output. abstract.inc shows each model’s output rate. The rates are fixed when you submit the request. The model field in every answer is the public id you sent.

Get started

Robot models

LLM models

Reference

Request

:async models

Buffered streaming

:superfast models

Idempotency-Key

OpenAI SDK

Usage

​Request

​:async models

​Buffered streaming

​:superfast models

​Idempotency-Key

​OpenAI SDK

​Usage

Request

:async models

Buffered streaming

:superfast models

Idempotency-Key

OpenAI SDK

Usage