costheta

costheta (costheta.dev) provides physically anchored, verifiable decisions for AI agents. A caller commits a hash of its options first; a subsequent cosmic-ray (muon) detector coincidence event enters the derivation, and the caller receives a dual-signed Ed25519 + ML-DSA (post-quantum) certificate from which anyone can recompute the outcome. It offers a free public beacon, paid decision and witness certificates ($0.02 per call settled in USDC via x402, no account or API key), a public SSE event stream, published verification keys and a native MCP server (costheta_random, costheta_decide, costheta_witness). Current certificates are single-node (one detector, one operator) with a federation-ready format. Operated by semnal.org from Constanta, Romania.

costheta publishes 13 API contracts indexed on the APIs.io network, including Dada API, Fast API, Federation API, and 10 more. Tagged areas include Company, Randomness, Verifiable Randomness, Cryptography, and Post-Quantum Cryptography.

The costheta catalog on APIs.io includes 1 JSON-LD context and 1 Spectral governance ruleset.

costheta’s developer surface includes authentication, documentation, and 23 more developer resources.

🌐 Visit website 📡 Profile data on GitHub

31.5/100 thin Agent 31/100 agent ready Full breakdown ↓
scored 2026-11-13 · rubric v0.28.0 · Show this score on your site →

AccessFreemiumOpen⚡ Free to try

2 published contracts 1 MCP Servers 2 Agent Skills

Company Randomness Verifiable Randomness Cryptography Post-Quantum Cryptography AI Agents MCP x402

Kin Score

Kin Score How this is scored →
scored 2026-11-13 · rubric v0.28.0

Composite quality — 31.5/100 · thin

Contract Quality 7.0 / 19

Developer Ergonomics 3.5 / 15

Access Clarity 2.6 / 15

Operational Transparency 3.0 / 10

Contract Governance 3.2 / 9

Discoverability 5.4 / 8

Regulatory Posture 1.6 / 15

Create-or-Update Ergonomics 0.0 / 10

Agent readiness — 31/100 · agent ready

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 0 / 6

MCP Server 12 / 12

Machine-Readable Auth 10 / 10

Idempotency 0 / 9

Stable Error Semantics 8 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 0 / 6

Agent Skills 5 / 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 applies to this provider. This API accepts writes, so it carries 10 points of the composite. It is scored from the published contracts themselves: whether a caller can create-or-update in one call, whether the write accepts a key the caller already holds, and whether the response says which branch ran. Without that, every write needs a search-and-branch in front of it, and the first time that check is skipped a duplicate record is created. Scored against the observed mean rather than raw — a provider at the catalog average is unchanged by this facet, not penalised by it.

The six quality facets above are damped to 75 points between them, because the conditional facet above carries the other 25. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 75% 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):

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) Ask about this →
A2A Agent Card +8 pts — a2a/-a2a.yml manifest, graded on conformance.grade against A2A 1.0.0 Ask about this →
Request/Response Examples +7 pts — share of operations carrying request/response examples; else an Examples / Code Samples link Ask about this →
Registration Without a Human +6 pts — a `registration_endpoint` in the served RFC 8414 / OIDC discovery document Ask about this →
Delegated User Identity +6 pts — a served discovery document listing authorization_code in grant_types_supported (served), else an oauth2 authorizationCode flow or openIdConnect declared in an OpenAPI (documented) Ask about this →
Typed Event Surface +6 pts — AsyncAPI document, OR webhooks/callbacks objects in the as-published OpenAPI, OR common[].type includes Webhooks Ask about this →

6 more unmet checks in the Agent Readiness table above.

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

Access Clarity scores 17.0 — up to +16.6 composite points Ask about this →
Contract Quality scores 37.5 — up to +15.6 composite points Ask about this →
Developer Ergonomics scores 23.2 — up to +15.4 composite points Ask about this →

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.

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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/costheta-dev/apis.yml: open an issue on github.com/api-evangelist/costheta-dev 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 →

Standards implemented 2

Standards this provider implements or carries. De facto ones are profiled and measured by the API Commons; formal ones come from the standards directory and are linked by the provider's own tags. The evidence column says how each claim was established — not that it was made.

Model Context Protocol (MCP)

measured — observed by APIs.io (documented)

OpenAPI

measured — observed by APIs.io (published)

APIs 13

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

costheta Dada API

The Dada API from costheta — 5 operation(s) for dada.

costheta Fast API

The FastAPI API from costheta — 2 operation(s) for fastapi.

costheta Federation API

The Federation API from costheta — 1 operation(s) for federation.

costheta Keys API

The Keys API from costheta — 1 operation(s) for keys.

costheta Llms.txt API

The Llms.txt API from costheta — 1 operation(s) for llms.txt.

costheta MCP API

The Mcp API from costheta — 1 operation(s) for mcp.

costheta Muon API

The Muon API from costheta — 4 operation(s) for muon.

costheta Pulse API

The Pulse API from costheta — 1 operation(s) for pulse.

costheta State API

The State API from costheta — 1 operation(s) for state.

costheta Stream API

The Stream API from costheta — 1 operation(s) for stream.

costheta Support.js API

The Support.js API from costheta — 1 operation(s) for support.js.

costheta V API

The V API from costheta — 1 operation(s) for v.

costheta Why API

The Why API from costheta — 1 operation(s) for why.

Scroll for all 13

MCP Servers 1

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

costheta MCP Server

MCP SERVER

Agent Skills 2

Packaged agent skills for driving this provider's APIs from an AI assistant.

costheta-observe-beacon

AGENT SKILL

costheta-verify-certificate

AGENT SKILL

costheta API pricing

Prices published by costheta.

Plan	Price
Free public beacon	costheta_random: free public beacon
Paid tools (costheta_decide, costheta_witness)	Paid tools: $0.02 per call, settled in USDC via x402.

Plan details, limits and sources →

Rate limits

Public event stream concurrent connections: Connection cap applies; over it, 503 with Retry-After.

Rate-limit details →

Pricing Plans 1

Published pricing tiers and plan structures.

costheta Plans Pricing

2 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

costheta Rate Limits

1 limits

RATE LIMITS

Semantic Vocabularies 1

JSON-LD contexts and semantic vocabularies used across these APIs.

Costheta Dev Context

2 classes · 6 properties

JSON-LD

Spectral Rules 1

Spectral governance rulesets for linting and validating these APIs. Counts are the severity each rule declares, not results of running them.

costheta API Rules

42 rules · 40 error-severity 1 warn-severity 1 info-severity

SPECTRAL

OpenAPI Overlays 1

Overlays applied on top of this provider's contracts. Each card says who wrote it: a document the provider publishes, or one API Evangelist derived or generated.

costheta Openapi Overlay

6 actions · documentation · costheta-dev-openapi.yml

GENERATED

Security Posture 2

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

costheta Authentication

2 schemes

SECURITY

costheta Domain Security

TLSv1.3

SECURITY

Agentic Access (API Evangelist recommendations) 1

Recommended x-agentic-access execution contracts for AI agents.

costheta Agentic Access

23 operations · 3 acting

AGENTIC

Resources

Documentation 1

Reference material describing how the API behaves

Documentation

Documentation

Agent Surfaces 5

MCP servers, agent skills, and machine-readable catalogs

MCPServer

AgenticAccess

AgentSkill

LLMsTxt

LLMsTxt

Design & Contract 8

Pagination, idempotency, versioning, errors, and events

Spectral

JSONLD

Vocabulary

DataModel

Conventions

Lifecycle

ErrorCatalog

Conformance

Scroll for all 8

Build 2

SDKs, sample code, and the tooling you integrate with

ToolCrosswalk

ToolCrosswalk

GitHubOrganization

GitHubOrganization

Access & Security 2

Authentication, authorization, and security posture

Authentication

Authentication

DomainSecurity

DomainSecurity

Operate 2

Status, limits, changes, and where to get help

RateLimits

RateLimits

Deprecation

Deprecation

Commercial 1

Pricing, plans, and the legal terms of use

Plans

Plans

Company 1

The organization behind the API

Website

Website

Other 3

Properties that don't map to a standard resource type

Overlay

Overlay

Hosts

Hosts

Vendors

Vendors

Source (apis.yml)

aid: costheta-dev
name: costheta
description: costheta (costheta.dev) provides physically anchored, verifiable decisions for AI agents. A caller commits a
  hash of its options first; a subsequent cosmic-ray (muon) detector coincidence event enters the derivation, and the caller
  receives a dual-signed Ed25519 + ML-DSA (post-quantum) certificate from which anyone can recompute the outcome. It offers
  a free public beacon, paid decision and witness certificates ($0.02 per call settled in USDC via x402, no account or API
  key), a public SSE event stream, published verification keys and a native MCP server (costheta_random, costheta_decide,
  costheta_witness). Current certificates are single-node (one detector, one operator) with a federation-ready format. Operated
  by semnal.org from Constanta, Romania.
url: https://artifacts.apis.io/costheta-dev/apis.yml
accessModel:
  pricing: freemium
  onboarding: open
  trial: false
  try_now: true
  public: true
  gated: none
  gated_source:
  - onboarding
  label: Freemium · Open access
  confidence: high
  probe_state: covered
  source:
  - plans
  - authentication
  - rate-limits
  - security
  generated: '2026-11-13'
  method: derived
image: https://costheta.dev/og-image.png
x-type: company
x-source: harvest:mcp-registry
x-tier: profiled
x-tier-reason: enrichment pass 2026-11-04 (modular-v1; was harvest)
specificationVersion: '0.20'
created: '2026-11-04'
modified: '2026-11-04'
tags:
- Company
- Randomness
- Verifiable Randomness
- Cryptography
- Post-Quantum Cryptography
- AI Agents
- MCP
- x402
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: MCPServer
  url: https://costheta.dev/mcp
- type: AgenticAccess
  url: agentic-access/costheta-dev-agentic-access.yml
- type: RateLimits
  url: rate-limits/costheta-dev-rate-limits.yml
- type: Plans
  url: plans/costheta-dev-plans-pricing.yml
- type: Spectral
  url: rules/costheta-dev-rules.yml
- type: JSONLD
  url: json-ld/costheta-dev-context.jsonld
- type: Vocabulary
  url: vocabulary/costheta-dev-vocabulary.yml
- type: AgentSkill
  url: skills/_index.yml
- type: DataModel
  url: data-model/costheta-dev-data-model.yml
- type: Conventions
  url: conventions/costheta-dev-conventions.yml
- type: Authentication
  url: authentication/costheta-dev-authentication.yml
- type: Deprecation
  url: lifecycle/costheta-dev-lifecycle.yml
- type: Lifecycle
  url: lifecycle/costheta-dev-lifecycle.yml
- type: ErrorCatalog
  url: errors/costheta-dev-problem-types.yml
- type: Conformance
  url: conformance/costheta-dev-conformance.yml
- type: Overlay
  url: overlays/costheta-dev-openapi-overlay.yaml
- type: LLMsTxt
  url: llms/costheta-dev-llms.txt
- type: ToolCrosswalk
  url: mcp/costheta-dev-tool-crosswalk.yml
- type: Hosts
  url: hosts/costheta-dev-hosts.yml
- type: Vendors
  url: vendors/costheta-dev-vendors.yml
- type: DomainSecurity
  url: security/costheta-dev-domain-security.yml
- type: Website
  url: https://costheta.dev/
- type: Documentation
  url: https://costheta.dev/why
- type: LLMsTxt
  url: https://costheta.dev/llms.txt
- type: GitHubOrganization
  url: https://github.com/costhetadev
apis:
- aid: costheta-dev:costheta-dev-dada-api
  name: costheta Dada API
  description: The Dada API from costheta — 5 operation(s) for dada.
  humanURL: https://costheta.dev/llms.txt
  baseURL: https://costheta.dev
  tags:
  - Dada
  properties:
  - type: OpenAPI
    url: openapi/costheta-dev-dada-api-openapi.yml
  - type: Documentation
    url: https://costheta.dev/why
- aid: costheta-dev:costheta-dev-fastapi-api
  name: costheta Fast API
  description: The FastAPI API from costheta — 2 operation(s) for fastapi.
  humanURL: https://costheta.dev/llms.txt
  baseURL: https://costheta.dev
  tags:
  - FastAPI
  properties:
  - type: OpenAPI
    url: openapi/costheta-dev-fastapi-api-openapi.yml
  - type: Documentation
    url: https://costheta.dev/why
- aid: costheta-dev:costheta-dev-federation-api
  name: costheta Federation API
  description: The Federation API from costheta — 1 operation(s) for federation.
  humanURL: https://costheta.dev/llms.txt
  baseURL: https://costheta.dev
  tags:
  - Federation
  properties:
  - type: OpenAPI
    url: openapi/costheta-dev-federation-api-openapi.yml
  - type: Documentation
    url: https://costheta.dev/why
- aid: costheta-dev:costheta-dev-keys-api
  name: costheta Keys API
  description: The Keys API from costheta — 1 operation(s) for keys.
  humanURL: https://costheta.dev/llms.txt
  baseURL: https://costheta.dev
  tags:
  - Keys
  properties:
  - type: OpenAPI
    url: openapi/costheta-dev-keys-api-openapi.yml
  - type: Documentation
    url: https://costheta.dev/why
- aid: costheta-dev:costheta-dev-llms-txt-api
  name: costheta Llms.txt API
  description: The Llms.txt API from costheta — 1 operation(s) for llms.txt.
  humanURL: https://costheta.dev/llms.txt
  baseURL: https://costheta.dev
  tags:
  - Llms.txt
  properties:
  - type: OpenAPI
    url: openapi/costheta-dev-llms-txt-api-openapi.yml
  - type: Documentation
    url: https://costheta.dev/why
- aid: costheta-dev:costheta-dev-mcp-api
  name: costheta MCP API
  description: The Mcp API from costheta — 1 operation(s) for mcp.
  humanURL: https://costheta.dev/llms.txt
  baseURL: https://costheta.dev
  tags:
  - MCP
  tags_raw:
  - Mcp
  properties:
  - type: OpenAPI
    url: openapi/costheta-dev-mcp-api-openapi.yml
  - type: Documentation
    url: https://costheta.dev/why
- aid: costheta-dev:costheta-dev-muon-api
  name: costheta Muon API
  description: The Muon API from costheta — 4 operation(s) for muon.
  humanURL: https://costheta.dev/llms.txt
  baseURL: https://costheta.dev
  tags:
  - Muon
  properties:
  - type: OpenAPI
    url: openapi/costheta-dev-muon-api-openapi.yml
  - type: Documentation
    url: https://costheta.dev/why
- aid: costheta-dev:costheta-dev-pulse-api
  name: costheta Pulse API
  description: The Pulse API from costheta — 1 operation(s) for pulse.
  humanURL: https://costheta.dev/llms.txt
  baseURL: https://costheta.dev
  tags:
  - Pulse
  properties:
  - type: OpenAPI
    url: openapi/costheta-dev-pulse-api-openapi.yml
  - type: Documentation
    url: https://costheta.dev/why
- aid: costheta-dev:costheta-dev-state-api
  name: costheta State API
  description: The State API from costheta — 1 operation(s) for state.
  humanURL: https://costheta.dev/llms.txt
  baseURL: https://costheta.dev
  tags:
  - States
  tags_raw:
  - State
  properties:
  - type: OpenAPI
    url: openapi/costheta-dev-state-api-openapi.yml
  - type: Documentation
    url: https://costheta.dev/why
- aid: costheta-dev:costheta-dev-stream-api
  name: costheta Stream API
  description: The Stream API from costheta — 1 operation(s) for stream.
  humanURL: https://costheta.dev/llms.txt
  baseURL: https://costheta.dev
  tags:
  - Stream
  properties:
  - type: OpenAPI
    url: openapi/costheta-dev-stream-api-openapi.yml
  - type: Documentation
    url: https://costheta.dev/why
- aid: costheta-dev:costheta-dev-support-js-api
  name: costheta Support.js API
  description: The Support.js API from costheta — 1 operation(s) for support.js.
  humanURL: https://costheta.dev/llms.txt
  baseURL: https://costheta.dev
  tags:
  - Support.js
  properties:
  - type: OpenAPI
    url: openapi/costheta-dev-support-js-api-openapi.yml
  - type: Documentation
    url: https://costheta.dev/why
- aid: costheta-dev:costheta-dev-v-api
  name: costheta V API
  description: The V API from costheta — 1 operation(s) for v.
  humanURL: https://costheta.dev/llms.txt
  baseURL: https://costheta.dev
  tags:
  - V
  properties:
  - type: OpenAPI
    url: openapi/costheta-dev-v-api-openapi.yml
  - type: Documentation
    url: https://costheta.dev/why
- aid: costheta-dev:costheta-dev-why-api
  name: costheta Why API
  description: The Why API from costheta — 1 operation(s) for why.
  humanURL: https://costheta.dev/llms.txt
  baseURL: https://costheta.dev
  tags:
  - Why
  properties:
  - type: OpenAPI
    url: openapi/costheta-dev-why-api-openapi.yml
  - type: Documentation
    url: https://costheta.dev/why
x-coverage:
  state: covered
  reason: identity-verified
  detail: Name, description and pointers taken from costheta.dev homepage (og:site_name "costheta", footer "operated by semnal.org
    · Constanta, Romania") and its llms.txt, which names github.com/costhetadev (org blog field = costheta.dev). No pricing,
    terms, privacy, support or blog pages are published; pricing is stated only inside llms.txt.
  evidence:
  - url: https://costheta.dev/
    status: 200
  - url: https://costheta.dev/llms.txt
    status: 200
  - url: https://costheta.dev/why
    status: 200
  - url: https://github.com/costhetadev
    status: 200
x-enrichment:
  date: '2026-11-04'
  status: enriched
  artifacts_added: 30
  pass: modular-v1
  engine: identity=anthropic,contract=anthropic,surfaces=anthropic,docs=anthropic,regulatory=anthropic

costheta API — frequently asked questions

Does costheta have an API?

Yes. APIs.io lists 13 APIs from costheta, including costheta Dada API, costheta Fast API and costheta Federation API, and 10 more.

Is there an OpenAPI specification for the costheta API?

Yes. APIs.io indexes 13 OpenAPI specifications for costheta, each linked for download from this page.

How do I authenticate with the costheta API?

costheta uses bearer-token authentication (2 schemes). The details are profiled on APIs.io as costheta Authentication.

How much does the costheta API cost?

costheta publishes its prices; its Free public beacon plan is costheta_random: free public beacon as of 2026-11-04. APIs.io lists 2 pricing plans for costheta, with each plan's price, limits and inclusions under Pricing on this page.

Does costheta have an MCP server?

Yes. APIs.io lists 1 MCP server for costheta.

Is the costheta API ready for AI agents?

costheta has a Kin Score of 31.5 out of 100 (thin) and an Agent Readiness score of 31.4 (agent-ready), scored by API Evangelist on 2026-11-13.

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