Asterlab

Aster (Aster AI Labs, PBC), operating as Asterlab, is a San Francisco based Y Combinator (Spring 2026) public benefit corporation building autonomous research systems that coordinate thousands of AI research agents working in parallel to automate open-ended scientific discovery. The company used that same autonomous-research system to optimize its own inference stack and now offers Aster Inference, an OpenAI-compatible inference API serving open-weight models (gpt-oss-120b, gpt-oss-120b-fast, and Z.ai's GLM 5.2) at what it benchmarks as the fastest gpt-oss-120b output speed on GPU (644 tok/s). The API works with the official OpenAI Python and JS SDKs, LangChain, LiteLLM, Cursor, the Vercel AI SDK, and most agent frameworks by pointing the base URL at https://api.asterlab.ai/v1, with zero data retention by default.

Asterlab is listed with 1 API on the APIs.io network. Tagged areas include Company, Artificial Intelligence, Machine Learning, LLM, and Inference.

Asterlab’s developer surface includes documentation, getting-started guide, pricing, signup flow, engineering blog, support, authentication, and 9 more developer resources.

🌐 Visit website 📡 Profile data on GitHub

33.0/100 thin ▬ flat Agent 3/100 human only Front door AI 3/6 light saas Full breakdown ↓
scored 2026-11-06 · rubric v0.27.0 · Show this score on your site →

AccessPaid

1 API

Company Artificial Intelligence Machine Learning LLM Inference OpenAI-CompatibleAutonomous ResearchGPU Developer Tools

Kin Score

Kin Score How this is scored →
scored 2026-11-06 · rubric v0.27.0

Composite quality — 33.0/100 · thin

Contract Quality 0.0 / 21

Developer Ergonomics 8.5 / 17

Access Clarity 13.0 / 17

Operational Transparency 0.0 / 11

Contract Governance 0.0 / 10

Discoverability 6.2 / 9

Regulatory Posture 2.7 / 15

Agent readiness — 3/100 · human only

Machine-Readable Contract 0 / 18

Agentic Access Contract 0 / 10

Documented Reversibility 0 / 6

MCP Server 0 / 12

Machine-Readable Auth 10 / 10

Idempotency 0 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 0 / 7

Typed Event Surface 0 / 6

Agent Skills 0 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 0 / 4

Delegated User Identity 0 / 6

Protected Resource Metadata 0 / 5

Registration Without a Human 0 / 6

Agentic Commerce Well-Known Document 0 / 5

Pagination 5 / 5

Distinct Operations 3 / 3

MCP Tool Quality 6 / 6

Regulatory Posture applies to this provider. Its tags matched the Horizontal (data, software, accessibility, platform) regime, so Regulatory Posture carries 15 points of the composite. If this regime is wrong for your business, say so on your provider repo — the applicability map is public and we will correct it.

Create-or-Update Ergonomics could not be measured. We hold no machine-readable contract for this provider to read, so there is nothing to measure a write surface against. Excluded rather than scored zero: never-measured and measured-empty are different facts. Publishing an OpenAPI is what makes this facet — and several others — scorable at all.

The six quality facets above are damped to 85 points between them, because the conditional facet above carries the other 15. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 85% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.

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Agent readiness — checks not met, largest first (exact, from this profile):

Machine-Readable Contract +18 pts — api_specs includes an OpenAPI document
MCP Server +12 pts — deployment.mode + probe verdict on the mcp/ manifest, not the pointer; an unprobed slug falls back to authorship
Agentic Access Contract +10 pts — agentic_access artifact present (x-agentic-access), graded by author
Idempotency +9 pts — OpenAPI mutating operations declare an idempotency key — a header, a request-body property, or a named de-duplication token whose own description says so (verified); else common[].type matches /idempoten/i (documented)
Stable Error Semantics +8 pts — OpenAPI $refs a shared error schema across 4xx/5xx responses (verified), else common[].type includes ErrorCatalog / ErrorCodes / DeclineCodes
A2A Agent Card +8 pts — a2a/-a2a.yml manifest, graded on conformance.grade against A2A 1.0.0

12 more unmet checks in the Agent Readiness table above.

Kin Score — facets with the most composite points still available (weight × headroom):

Contract Quality scores 0.0 — up to +25.0 composite points
Operational Transparency scores 0.0 — up to +13.0 composite points
Contract Governance scores 0.0 — up to +12.0 composite points

Each check links to what satisfies it. Publish the artifact, or tell us where it already lives, and the score moves on the next scoring run.

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. Every facet and dimension name above is a link: it opens that measurement's own page — what it means, the exact checks that feed it, how the whole catalog distributes on it, and the providers at the top of it. This rating is computed from the provider profile at artifacts.apis.io/asterlab/apis.yml: open an issue on github.com/api-evangelist/asterlab to ask a question or point us at an artifact you publish. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

APIs 1

Individual APIs this provider publishes, each with its own machine-readable definition.

Aster Inference API

OpenAI-compatible inference API from Aster serving open-weight models (gpt-oss-120b, gpt-oss-120b-fast, GLM 5.2). Authenticate with an Aster API key created in the inference con...

Asterlab API pricing

Prices published by Asterlab, read 2026-10-07 from www.asterlab.ai/inference.

Plan	Price
gpt-oss-120b-fast	Input $0.30 per M tokens
gpt-oss-120b-fast output	Output $1.20 per M tokens
Kimi K3 input	Input $2.50 per M tokens
Kimi K3 output	Output $12.50 per M tokens
GLM 5.2 input	Input $1.00 per M tokens
GLM 5.2 output	Output $4.00 per M tokens

Plan details, limits and sources →

Pricing Plans 1

Published pricing tiers and plan structures.

Asterlab Plans Pricing

6 plans

PLANS

Security Posture 2

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Asterlab Authentication

http · 1 scheme

SECURITY

Asterlab Domain Security

TLSv1.3 · HSTS

SECURITY

Resources

Get Started 3

Portal, sign-up, and the first successful call

DeveloperPortal

DeveloperPortal

GettingStarted

GettingStarted

SignUp

SignUp

Documentation 1

Reference material describing how the API behaves

Documentation

Documentation

Agent Surfaces 2

MCP servers, agent skills, and machine-readable catalogs

WellKnown

WellKnown

LLMsTxt

LLMsTxt

Design & Contract 1

Pagination, idempotency, versioning, errors, and events

Conventions

Conventions

Access & Security 2

Authentication, authorization, and security posture

Authentication

Authentication

DomainSecurity

DomainSecurity

Operate 1

Status, limits, changes, and where to get help

Support

Support

Commercial 4

Pricing, plans, and the legal terms of use

Plans

Pricing

TermsOfService

PrivacyPolicy

Company 2

The organization behind the API

Website

Website

Blog

Blog

Source (apis.yml)

aid: asterlab
name: Asterlab
description: Aster (Aster AI Labs, PBC), operating as Asterlab, is a San Francisco based Y Combinator (Spring 2026) public
  benefit corporation building autonomous research systems that coordinate thousands of AI research agents working in parallel
  to automate open-ended scientific discovery. The company used that same autonomous-research system to optimize its own inference
  stack and now offers Aster Inference, an OpenAI-compatible inference API serving open-weight models (gpt-oss-120b, gpt-oss-120b-fast,
  and Z.ai's GLM 5.2) at what it benchmarks as the fastest gpt-oss-120b output speed on GPU (644 tok/s). The API works with
  the official OpenAI Python and JS SDKs, LangChain, LiteLLM, Cursor, the Vercel AI SDK, and most agent frameworks by pointing
  the base URL at https://api.asterlab.ai/v1, with zero data retention by default.
deliveryModel:
  model: saas
  open_source: false
  commercial: true
  callable_host: false
  label: Hosted service · you call their endpoint
  confidence: medium
  source:
  - pricing
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: paid
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Paid
  confidence: medium
  source:
  - plans
  - authentication
  - security
  generated: '2026-11-06'
  method: derived
image: https://www.asterlab.ai/og/default.png
url: https://raw.githubusercontent.com/api-evangelist/asterlab/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- y-combinator
x-tier: stub
x-tier-reason: portfolio-lead
specificationVersion: '0.23'
created: '2026-07-17'
modified: '2026-07-18'
tags:
- Company
- Artificial Intelligence
- Machine Learning
- LLM
- Inference
- OpenAI-Compatible
- Autonomous Research
- GPU
- Developer Tools
tags_raw:
- Company
- Artificial Intelligence
- Machine Learning
- LLM
- Inference
- OpenAI Compatible
- Autonomous Research
- GPU
- Developer Tools
- Machine-Learning
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
apis:
- name: Aster Inference API
  description: OpenAI-compatible inference API from Aster serving open-weight models (gpt-oss-120b, gpt-oss-120b-fast, GLM
    5.2). Authenticate with an Aster API key created in the inference console and set the base URL to https://api.asterlab.ai/v1;
    works with the OpenAI SDKs, LangChain, LiteLLM, and most agent frameworks. Zero data retention by default.
  humanURL: https://www.asterlab.ai/inference
  baseURL: https://api.asterlab.ai/v1
  tags:
  - Inference
  - LLM
  - OpenAI-Compatible
  tags_raw:
  - Inference
  - LLM
  - OpenAI Compatible
  properties:
  - type: Authentication
    url: authentication/asterlab-authentication.yml
  - type: Conventions
    url: conventions/asterlab-conventions.yml
common:
- type: Plans
  url: plans/asterlab-plans-pricing.yml
- type: Website
  url: https://www.asterlab.ai/
- type: DeveloperPortal
  url: https://www.asterlab.ai/inference/console
- type: Documentation
  url: https://www.asterlab.ai/inference
- type: GettingStarted
  url: https://www.asterlab.ai/inference
- type: Pricing
  url: https://www.asterlab.ai/inference
- type: SignUp
  url: https://www.asterlab.ai/inference/console
- type: TermsOfService
  url: https://www.asterlab.ai/terms
- type: PrivacyPolicy
  url: https://www.asterlab.ai/privacy
- type: Blog
  url: https://www.asterlab.ai/research/scaling_autonomous_research_to_thousands_of_agents
- type: Support
  url: mailto:info@asterlab.ai
- type: Authentication
  url: authentication/asterlab-authentication.yml
- type: Conventions
  url: conventions/asterlab-conventions.yml
- type: WellKnown
  url: well-known/asterlab-well-known.yml
- type: LLMsTxt
  url: llms/asterlab-llms.txt
- type: DomainSecurity
  url: security/asterlab-domain-security.yml
x-enrichment:
  date: '2026-07-19'
  status: backfilled
  pass: local-v1
  note: backfilled from .gitignore signal + verified work evidence

Asterlab API — frequently asked questions

Does Asterlab have an API?

Yes. APIs.io lists 1 API from Asterlab, including Aster Inference API.

How do I authenticate with the Asterlab API?

Asterlab uses bearer-token authentication (http · 1 scheme). The details are profiled on APIs.io as Asterlab Authentication.

How much does the Asterlab API cost?

Asterlab publishes its prices; its gpt-oss-120b-fast plan is Input $0.30 per M tokens as of 2026-10-07. APIs.io lists 6 pricing plans for Asterlab, with each plan's price, limits and inclusions under Pricing on this page.

Is the Asterlab API ready for AI agents?

Asterlab has a Kin Score of 33.0 out of 100 (thin) and an Agent Readiness score of 2.5 (human-only), scored by API Evangelist on 2026-11-06.

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