Perseus

Perseus (legal name Efficient Systems Inc.) is an applied AI lab focused on semantic search in latent spaces, founded by Samrath Chadha and backed by Y Combinator (Fall 2025 batch). Its first product is a retrieval engine that grounds coding agents in real code: developers and agents describe the code they are looking for in plain English and Perseus returns ranked file:line results with snippets in seconds, indexing the working tree (including uncommitted edits) so models like Claude Code, Cursor, and Codex can find the right context before editing. Rather than a public REST API, Perseus ships a first-party CLI (installed via a curl/PowerShell one-liner, as a PyInstaller binary or uv wheel), a provider-published Agent Skill, and a Factory Droid plugin, all under the efficientsystemsinc GitHub organization. The developer surface — docs, console, pricing, and blog — is live; there is no OpenAPI, MCP server, or /.well-known discovery document published as of this pass.

Perseus is profiled on the APIs.io network. Tagged areas include Company, Artificial Intelligence, Developer Tools, Code Search, and Semantic Search.

Perseus’ developer surface includes documentation, getting-started guide, pricing, engineering blog, signup flow, support, CLI, and 7 more developer resources.

🌐 Visit website 📡 Source on GitHub

23.9/100 emerging ▬ flat Agent 14/100 human only Full breakdown ↓
scored 2026-07-23 · rubric v0.5

0 APIs

CompanyArtificial IntelligenceDeveloper ToolsCode SearchSemantic SearchCoding AgentsAI AgentsLatent SpaceCLIAgent SkillsY Combinator

Kin Score

Kin Score How this is scored →
scored 2026-07-23 · rubric v0.5

Composite quality — 23.9/100 · emerging

Contract Quality 0.0 / 25

Developer Ergonomics 11.7 / 20

Commercial Clarity 4.7 / 20

Operational Transparency 0.7 / 13

Governance 0.0 / 12

Discoverability 6.8 / 10

Agent readiness — 14/100 · human only

Machine-Readable Contract 0 / 18

Agentic Access Contract 0 / 15

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 5 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/perseus: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

Get Started 3

Portal, sign-up, and the first successful call

GettingStarted

GettingStarted

DeveloperPortal

DeveloperPortal

SignUp

SignUp

Documentation 1

Reference material describing how the API behaves

Documentation

Documentation

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

AgentSkill

AgentSkill

Build 3

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

GitHubOrganization

CLI

CLI

Packages

Packages

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 1

Pricing, plans, and the legal terms of use

Pricing

Pricing

Company 2

The organization behind the API

Website

Website

Blog

Blog

Source (apis.yml)

aid: perseus
accessModel:
  pricing: unknown
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Unknown
  confidence: low
  source:
  - authentication
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/perseus.png
name: Perseus
description: 'Perseus (legal name Efficient Systems Inc.) is an applied AI lab focused on semantic search in latent spaces,
  founded by Samrath Chadha and backed by Y Combinator (Fall 2025 batch). Its first product is a retrieval engine that grounds
  coding agents in real code: developers and agents describe the code they are looking for in plain English and Perseus returns
  ranked file:line results with snippets in seconds, indexing the working tree (including uncommitted edits) so models like
  Claude Code, Cursor, and Codex can find the right context before editing. Rather than a public REST API, Perseus ships a
  first-party CLI (installed via a curl/PowerShell one-liner, as a PyInstaller binary or uv wheel), a provider-published Agent
  Skill, and a Factory Droid plugin, all under the efficientsystemsinc GitHub organization. The developer surface — docs,
  console, pricing, and blog — is live; there is no OpenAPI, MCP server, or /.well-known discovery document published as of
  this pass.'
url: https://raw.githubusercontent.com/api-evangelist/perseus/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: '0.20'
created: '2026-07-17'
modified: '2026-07-20'
tags:
- Company
- Artificial Intelligence
- Developer Tools
- Code Search
- Semantic Search
- Coding Agents
- AI Agents
- Latent Space
- CLI
- Agent Skills
- Y Combinator
x-enrichment:
  date: '2026-07-20'
  status: enriched
  artifacts_added: 6
  pass: local-v1
apis: []
common:
- type: Website
  url: https://perseus.computer
- type: Documentation
  url: https://perseus.computer/docs
- type: GettingStarted
  url: https://perseus.computer/docs
- type: DeveloperPortal
  url: https://perseus.computer/console
- type: Pricing
  url: https://perseus.computer/pricing
- type: Blog
  url: https://perseus.computer/blog
- type: SignUp
  url: https://perseus.computer/console/onboarding?plan=developer_monthly
- type: Support
  url: mailto:hello@perseus.computer
- type: GitHubOrganization
  url: https://github.com/efficientsystemsinc
- type: CLI
  url: cli/perseus-cli.yml
- type: AgentSkill
  url: skills/perseus-code-search.md
- type: Packages
  url: packages/perseus-packages.yml
- type: Authentication
  url: authentication/perseus-authentication.yml
- type: DomainSecurity
  url: security/perseus-domain-security.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io