Linzumi

Linzumi is a Y Combinator (Spring 2026) company in San Francisco building a Slack-shaped team chat that runs a fleet of AI coding agents inside every channel. Engineering teams kick off work, watch agent activity in real time, review output, and ship code without leaving the thread. Unlike sandboxed cloud agent products, Linzumi runs agents on the developer's own machine through a local "Commander" runner installed from the @linzumi/cli npm package, so agents work against real environment variables, dotfiles, and branches inside explicitly trusted folders. The product adds a decision inbox that surfaces only the choices needing a human, continuously compiled team context, git safety snapshots taken before each agent turn, and a bundled local MCP server that lets coding agents read scoped Linzumi message, thread, and channel context. It supports OpenAI Codex today with Claude Code announced as coming soon. The service is in beta via a macOS desktop app and a web workspace; there is no public developer API program, documentation portal, or published OpenAPI at this time.

Linzumi publishes 1 API on the APIs.io network. Tagged areas include Company, Artificial Intelligence, Developer Tools, Coding Agents, and Team Chat.

Linzumi’s developer surface includes support, CLI, authentication, changelog, and 11 more developer resources.

🌐 Visit website 📡 Source on GitHub

15.7/100 emerging ▬ flat Agent 5/100 agent aware saas Full breakdown ↓
scored 2026-09-08 · rubric v0.20.0

AccessSelf serve

1 APIs 1 MCP Servers

Company Artificial Intelligence Developer Tools Coding Agents Team Chat Collaboration MCP Command Line Interface Y Combinator

Kin Score

Kin Score How this is scored →
scored 2026-09-08 · rubric v0.20.0

Composite quality — 15.7/100 · emerging

Contract Quality 0.0 / 25

Developer Ergonomics 4.8 / 20

Access Clarity 1.3 / 20

Operational Transparency 2.1 / 13

Contract Governance 0.0 / 12

Discoverability 7.6 / 10

Agent readiness — 5/100 · agent aware

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 8 / 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

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.

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 github.com/api-evangelist/linzumi: open an issue to ask a question, or submit a pull request to add artifacts. 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.

Linzumi Runner API

The private product API behind the Linzumi web workspace and the local Commander runner, served from serve.linzumi.com under a /api/v2 URI-versioned path. It is not a published ...

MCP Servers 1

Model Context Protocol servers that expose these APIs to AI agents.

Linzumi MCP Server

MCP SERVER

Security Posture 2

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

Linzumi Authentication

oauth2-device-code/oauth2-authorization-code · 3 schemes

SECURITY

Linzumi Domain Security

TLSv1.3 · DNSSEC · DMARC

SECURITY

Resources

Get Started 1

Portal, sign-up, and the first successful call

Login

Agent Surfaces 2

MCP servers, agent skills, and machine-readable catalogs

MCPServer

MCPServer

LLMsTxt

LLMsTxt

Design & Contract 3

Pagination, idempotency, versioning, errors, and events

Conventions

Conventions

ErrorCatalog

ErrorCatalog

Lifecycle

Lifecycle

Build 2

SDKs, sample code, and the tooling you integrate with

Packages

Packages

CLI

CLI

Access & Security 2

Authentication, authorization, and security posture

Authentication

Authentication

DomainSecurity

DomainSecurity

Operate 2

Status, limits, changes, and where to get help

Support

Support

ChangeLog

ChangeLog

Company 1

The organization behind the API

Website

Website

Other 2

Properties that don't map to a standard resource type

Download

Download

Profile

Profile

Source (apis.yml)

aid: linzumi
name: Linzumi
description: Linzumi is a Y Combinator (Spring 2026) company in San Francisco building a Slack-shaped team chat that runs
  a fleet of AI coding agents inside every channel. Engineering teams kick off work, watch agent activity in real time, review
  output, and ship code without leaving the thread. Unlike sandboxed cloud agent products, Linzumi runs agents on the developer's
  own machine through a local "Commander" runner installed from the @linzumi/cli npm package, so agents work against real
  environment variables, dotfiles, and branches inside explicitly trusted folders. The product adds a decision inbox that
  surfaces only the choices needing a human, continuously compiled team context, git safety snapshots taken before each agent
  turn, and a bundled local MCP server that lets coding agents read scoped Linzumi message, thread, and channel context. It
  supports OpenAI Codex today with Claude Code announced as coming soon. The service is in beta via a macOS desktop app and
  a web workspace; there is no public developer API program, documentation portal, or published OpenAPI at this time.
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: unknown
  onboarding: self-serve
  trial: false
  try_now: false
  public: false
  label: Self-serve signup
  confidence: medium
  source:
  - authentication
  generated: '2026-07-22'
  method: derived
image: https://storage.googleapis.com/ployai/d195dfe3-6a0f-4051-8d67-1a4376685f60/user/3e1aeaf5-og-home-en.jpg
url: https://raw.githubusercontent.com/api-evangelist/linzumi/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- y-combinator
x-tier: profiled
x-tier-reason: enriched-from-public-sources
specificationVersion: '0.23'
created: '2026-07-17'
modified: '2026-07-19'
tags:
- Company
- Artificial Intelligence
- Developer Tools
- Coding Agents
- Team Chat
- Collaboration
- MCP
- Command Line Interface
- Y Combinator
apis:
- aid: linzumi:runner-api
  name: Linzumi Runner API
  description: The private product API behind the Linzumi web workspace and the local Commander runner, served from serve.linzumi.com
    under a /api/v2 URI-versioned path. It is not a published developer API — there is no portal, reference, or OpenAPI —
    but it is partially observable through the publicly published @linzumi/cli client, which documents the device-authorization
    endpoint and speaks WebSocket to wss://serve.linzumi.com for runner traffic. Captured here as an observed surface, not
    a supported public contract.
  humanURL: https://www.npmjs.com/package/@linzumi/cli
  baseURL: https://serve.linzumi.com/api/v2
  tags:
  - Coding Agents
  - Team Chat
  properties:
  - type: Authentication
    url: authentication/linzumi-authentication.yml
  - type: Conventions
    url: conventions/linzumi-conventions.yml
  - type: ErrorCatalog
    url: errors/linzumi-problem-types.yml
common:
- type: Website
  url: https://linzumi.com/
- type: Login
  url: https://serve.linzumi.com/
- type: Support
  url: mailto:hello@linzumi.com
- type: Download
  url: https://downloads.linzumi.com/macos-beta/linzumi_macos_latest.dmg
- type: Profile
  url: https://www.ycombinator.com/companies/linzumi
- type: Packages
  url: packages/linzumi-packages.yml
- type: CLI
  url: cli/linzumi-cli.yml
- type: MCPServer
  url: mcp/linzumi-mcp.yml
- type: Authentication
  url: authentication/linzumi-authentication.yml
- type: Conventions
  url: conventions/linzumi-conventions.yml
- type: ErrorCatalog
  url: errors/linzumi-problem-types.yml
- type: Lifecycle
  url: lifecycle/linzumi-lifecycle.yml
- type: ChangeLog
  url: changelog/linzumi-changelog.yml
- type: DomainSecurity
  url: security/linzumi-domain-security.yml
- type: LLMsTxt
  url: llms/linzumi-llms.txt
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
x-enrichment:
  date: '2026-07-19'
  status: backfilled
  pass: local-v1
  note: backfilled from .gitignore signal + verified work evidence

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