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tessl.io

Tessl is an agent-enablement platform for spec-driven and agentic software development. It provides a registry of versioned "tiles"/plugins (10,000+ library docs) and 3,000+ searchable Agent Skills, a CLI for authoring, linting, reviewing, and publishing skills and plugins, server-side quality reviews and Snyk-powered security scanning, eval/scenario tooling to prove a skill changes agent behavior, org/workspace governance with install policies, and a first-party Model Context Protocol (MCP) server plus a workspace MCP gateway so AI coding agents can discover and install the right context. Backed by Index Ventures. The public REST API (api.tessl.io) exposes 225 operations across tiles, skills, workspaces, orgs, projects, evals, and integrations.

agent native

Real signal across most facets with visible, nameable gaps — the contract exists but is thin, or the portal is good while governance and commercial terms are absent.

Kin Score
travel_explore apis.io index code GitHub sourcepublic Website

API Evangelist profiles tessl.io the way a machine reads it — 74 machine-readable artifacts across 1 API, pulled from the provider's own public surface and indexed so a developer, an analyst, or an AI agent can evaluate it against every other provider on the network.

Every provider in the network is reduced to the same set of machine-readable artifacts — OpenAPI contracts, event specifications, GraphQL schemas, runnable collections, pricing and rate-limit signals, security posture, OAuth scopes, and the agent surfaces (MCP servers and skills) that let software drive the API on its own. We profile them because the interface is the part of a company you can actually inspect: it is a truer signal of what a provider does than any marketing page. From those artifacts we compute the Kin Score — tessl.io scores 48.5/100 (developing), with a separate agent-readiness read of 40/100 (agent native). The full breakdown is below, followed by every artifact we hold — each card links through to its machine-readable definition on apis.io.

Kin Score

This is the API Evangelist rating — a single, repeatable read computed from the artifacts on this page. Green fill is points earned; the red track is points possible, so every bar shows earned-versus-possible at a glance. Every facet and dimension name is a link: it opens that measurement's page on APIs.io, where the rating runs across the whole catalog — the exact checks that feed it, how every profiled provider distributes on it, and who is at the top of it.

Kin Score Kin Score How this is scored →
scored 2026-09-08 · rubric v0.20.0
Composite quality — 48.5/100 · developing
Contract Quality 11.6 / 25
Developer Ergonomics 14.6 / 20
Access Clarity 3.7 / 20
Operational Transparency 6.2 / 13
Contract Governance 0.5 / 12
Discoverability 7.6 / 10
Agent readiness — 40/100 · agent native
Machine-Readable Contract 18 / 18
Agentic Access Contract derived 2.5 / 10
Documented Reversibility 6.0 / 6
MCP Server documented 4.8 / 12
Machine-Readable Auth bearer 3.5 / 10
Idempotency 9.0 / 9
Stable Error Semantics documented 4.0 / 8
Request/Response Examples 7.0 / 7
Rate-Limit Signaling 0 / 7
Typed Event Surface 0 / 6
Agent Skills derived 1.3 / 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
tessl.io Kin Score — API readiness rating by API Evangelist

Put this on your own site. The badge is drawn live from tessl.io's current Kin Score — paste it once and it updates itself every time the score is recomputed. It follows your visitor's light or dark setting, and it links back here so anyone who sees it can read the full breakdown.

<!-- Kin Score · API Evangelist -->
<a href="https://providers.apievangelist.com/providers/tesslio/"
   title="tessl.io on API Evangelist — API profile and Kin Score">
  <img src="https://apis.io/badge/tesslio.svg"
       alt="tessl.io Kin Score — API readiness rating by API Evangelist" width="150" height="150" loading="lazy">
</a>

More shapes, themes and sizes → · Score as JSON · How badges work

How we profile tessl.io

Each block below is one kind of artifact we hold for tessl.io. For each we say what it is and why it earns a place in the profile, then list every one we've indexed — capped at two rows, scroll within the panel for the rest.

APIs 35

Each API is captured as its own OpenAPI definition — every operation, parameter, and response. This is the single most useful machine-readable description of what an API does, and it's what lets us score, lint, mock, and generate against it without asking the provider for anything.

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

tessl.io Admin Keys API

Admin-scoped API keys for support tooling.

tessl.io Agent Logs API

Agent and hosted-execution log uploads.

tessl.io API Keys API

Workspace and organization API keys.

tessl.io Badges API

Workspace badge generation.

tessl.io Billing API

The Billing API from tessl.io — 4 operation(s) for billing.

tessl.io Capacity API

Sandbox and capacity-lease scheduling.

tessl.io CLI API

Endpoints used by the Tessl CLI.

tessl.io Context API

The Context API from tessl.io — 3 operation(s) for context.

tessl.io Curated Lists API

Curated tile lists and items.

tessl.io Environments API

The Environments API from tessl.io — 2 operation(s) for environments.

tessl.io Evals API

Eval runs, scenarios, and solution scoring.

tessl.io Fix Runs API

The Fix Runs API from tessl.io — 4 operation(s) for fix runs.

tessl.io Generation API

Eval scenario generation runs.

tessl.io InstallPolicy API

The InstallPolicy API from tessl.io — 2 operation(s) for installpolicy.

tessl.io Integrations API

Third-party integrations (GitHub, GitLab, etc).

tessl.io Launch Runs API

The Launch Runs API from tessl.io — 4 operation(s) for launch runs.

tessl.io LLM API

The LLM API from tessl.io — 2 operation(s) for llm.

tessl.io ManagedProjectPolicy API

The ManagedProjectPolicy API from tessl.io — 1 operation(s) for managedprojectpolicy.

tessl.io MCP API

The MCP API from tessl.io — 4 operation(s) for mcp.

tessl.io Orgs API

Organizations, members, and invitations.

tessl.io Policy API

The Policy API from tessl.io — 3 operation(s) for policy.

tessl.io Projects API

Workspace projects.

tessl.io PublishPolicy API

The PublishPolicy API from tessl.io — 1 operation(s) for publishpolicy.

tessl.io Repos API

Source-control repository helpers.

tessl.io Review Runs API

The Review Runs API from tessl.io — 3 operation(s) for review runs.

tessl.io Reviews API

The Reviews API from tessl.io — 3 operation(s) for reviews.

tessl.io Search API

Search across tiles, skills, and repos.

tessl.io Security Review Runs API

The Security Review Runs API from tessl.io — 2 operation(s) for security review runs.

tessl.io SkillInventory API

The SkillInventory API from tessl.io — 24 operation(s) for skillinventory.

tessl.io Skills API

Skill discovery, reviews, and security checks.

tessl.io Tasks API

The Tasks API from tessl.io — 8 operation(s) for tasks.

tessl.io Tiles API

Tile catalog, versions, and metadata.

tessl.io Users API

User accounts and identity.

tessl.io Workflows API

Background workflow executions and repository workflow configs.

tessl.io Workspaces API

Workspaces and workspace membership.

Scroll within the panel for all 35 ·

Open Collections 33

Open, tool-agnostic collections carry the same runnable value as Postman without locking you to one client — the portable, forkable form of the same exercise.

Open, tool-agnostic API collections (OpenAPI-derived and Bruno).

API Collection

OPEN COLLECTION

Tessl Admin Keys API

OPEN COLLECTION

Tessl Admin Keys Agent Logs API

OPEN COLLECTION

Tessl Admin Keys API Keys API

OPEN COLLECTION

Tessl Admin Keys Badges API

OPEN COLLECTION

Tessl Admin Keys Billing API

OPEN COLLECTION

Tessl Admin Keys Capacity API

OPEN COLLECTION

Tessl Admin Keys CLI API

OPEN COLLECTION

Tessl Admin Keys Context API

OPEN COLLECTION

Tessl Admin Keys Curated Lists API

OPEN COLLECTION

Tessl Admin Keys Environments API

OPEN COLLECTION

Tessl Admin Keys Evals API

OPEN COLLECTION

Tessl Admin Keys Fix Runs API

OPEN COLLECTION

Tessl Admin Keys Generation API

OPEN COLLECTION

Tessl Admin Keys InstallPolicy API

OPEN COLLECTION

Tessl Admin Keys Integrations API

OPEN COLLECTION

Tessl Admin Keys Launch Runs API

OPEN COLLECTION

Tessl Admin Keys LLM API

OPEN COLLECTION

Tessl Admin Keys ManagedProjectPolicy API

OPEN COLLECTION

Tessl Admin Keys MCP API

OPEN COLLECTION

Tessl Admin Keys Orgs API

OPEN COLLECTION

Tessl Admin Keys Policy API

OPEN COLLECTION

Tessl Admin Keys Projects API

OPEN COLLECTION

Tessl Admin Keys PublishPolicy API

OPEN COLLECTION

Tessl Admin Keys Repos API

OPEN COLLECTION

Tessl Admin Keys Search API

OPEN COLLECTION

Tessl Admin Keys SkillInventory API

OPEN COLLECTION

Tessl Admin Keys Skills API

OPEN COLLECTION

Tessl Admin Keys Tasks API

OPEN COLLECTION

Tessl Admin Keys Tiles API

OPEN COLLECTION

Tessl Admin Keys Users API

OPEN COLLECTION

Tessl Admin Keys Workflows API

OPEN COLLECTION

Tessl Admin Keys Workspaces API

OPEN COLLECTION

Scroll within the panel for all 33 ·

MCP Servers 1

Model Context Protocol servers expose these APIs directly to AI agents. We profile them because agent-native access is the fastest-growing way this provider's capabilities actually get used.

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

tessl.io MCP Server

MCP SERVER

Security Posture 4

Authentication, domain security, vulnerability disclosure, and trust-center signals — the evidence that a provider takes security seriously enough to document it. We profile it because you can't govern what you can't see.

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

Tesslio Authentication

http-bearer/apiKey/oauth2 · 4 schemes

SECURITY

Tesslio Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Tesslio Vulnerability Disclosure

security.txt · contact published

SECURITY

Tesslio Trust Center

trust center published

SECURITY

Agentic Access 1

An x-agentic-access contract marks which operations are safe for an agent to run on its own and which need a human in the loop. It is the difference between an API an agent can use and one it can use safely.

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

Tesslio Agentic Access

225 operations · 111 acting · 19 human-in-the-loop

225 operations · 111 acting

AGENTIC

Resources

Every other property we hold for tessl.io — documentation, portals, status pages, policies, and corporate surface — grouped by the job it does, following the integrator's arc from getting started to running in production.

Get Started 4

Portal, sign-up, and the first successful call

DeveloperPortal
DeveloperPortal
 GettingStarted
GettingStarted
 SignUp
SignUp
 Registry
Registry

Documentation 3

Reference material describing how the API behaves

OpenAPI
OpenAPI
 Documentation
Documentation
 APIReference
APIReference

Agent Surfaces 5

MCP servers, agent skills, and machine-readable catalogs

MCPServer
MCPServer
 AgentSkill
AgentSkill
 AgenticAccess
AgenticAccess
 WellKnown
WellKnown
 LLMsTxt
LLMsTxt

Design & Contract 5

Pagination, idempotency, versioning, errors, and events

Conventions
Conventions
 ErrorCatalog
ErrorCatalog
 DataModel
DataModel
 Conformance
Conformance
 Lifecycle
Lifecycle

Build 4

SDKs, sample code, and the tooling you integrate with

CLI
CLI
 Packages
Packages
 SDKs
SDKs
 GitHubOrganization
GitHubOrganization

Access & Security 6

Authentication, authorization, and security posture

Authentication
Authentication
 SecurityTxt
SecurityTxt
 VulnerabilityDisclosure
VulnerabilityDisclosure
 Security
Security
 DomainSecurity
DomainSecurity
 TrustCenter
TrustCenter

Operate 4

Status, limits, changes, and where to get help

StatusPage
StatusPage
 Deprecation
Deprecation
 ChangeLog
ChangeLog
 Support
Support

Commercial 1

Pricing, plans, and the legal terms of use

Pricing
Pricing

Company 2

The organization behind the API

Blog
Blog
 Website
Website

Other 2

Properties that don't map to a standard resource type

CapabilityMap
CapabilityMap
 Overlay
Overlay

← All providers · Data indexed from github.com/api-evangelist/tesslio · machine-readable index on apis.io

Where this information came from

This is an independent, third-party profile of tessl.io, published by API Evangelist. We do not operate, host, resell, or support these APIs, and we are not affiliated with or endorsed by the company unless stated above. Everything here is built from publicly available information — the company's own site, developer portal, documentation, public repositories, and the specifications it publishes for public use. Nothing is obtained by breaching a system, defeating an access control, or using credentials.

The Kin Score and Agent Readiness rating are independently calculated assessments of a company's public API artifacts, scored against a published rubric. They are not certifications, endorsements, security assessments, or audits.

Corrections, re-scores, and removal are free — no partnership or purchase required, and you do not need to justify the request. A removed company is recorded as unrated, never scored zero for having asked. Acknowledgement within one business day; removal within two.

info@apievangelist.com · Read the full data-sourcing policy →
On a security or compliance team? Put security in the subject line and you will get a person, not a form — we will tell you exactly which public URLs this profile was built from.