VASTlint MCP Server

io.github.aleksUIX/vastlint

answering

VASTlint is answering right now. Last checked 8 min ago. It exposes 14 tools. Last commit 2 Aug 2026.

Validate VAST, VMAP, and DAAST ad tags against IAB specs. 220 rules, pure Rust core.

Uptime history 44 hours of history

44 hours agonow

100.0%

Uptime 24h

91 of 91 checks

Tools

read from the server

118 ms

Response time

average over 24h

Stars

last commit 2 Aug 2026

Connect this server

Endpoint below is the one we actually reach during checks — not the one copied from a README. Last verified 8 min ago.

Claude Code Claude Desktop Codex Cursor VS Code

run in your terminal

claude mcp add vastlint --transport http https://vastlint.org/mcp

~/Library/Application Support/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "vastlint": {
      "url": "https://vastlint.org/mcp"
    }
  }
}

~/.codex/config.toml

[mcp_servers.vastlint]
url = "https://vastlint.org/mcp"

.cursor/mcp.json

{
  "mcpServers": {
    "vastlint": {
      "url": "https://vastlint.org/mcp"
    }
  }
}

.vscode/mcp.json

{
  "mcpServers": {
    "vastlint": {
      "url": "https://vastlint.org/mcp"
    }
  }
}

Available tools 14

Read directly from the server with tools/list, grouped by what they act on. If a tool disappears, we record the date.

content

create_content_standards

AdCP content-standards specialism. Creates a new set of content quality policies for a brand. Policies include brand safety rules, imagery quality requirements, and compliance constraints. Returns a standards_id that can be used with calibrate_content and validate_content_delivery. Requires Bearer authentication.

delete_content_standards

AdCP content-standards specialism. Permanently removes a content standard set. Callers relying on the standards_id for calibrate_content or validate_content_delivery should retire those integrations first. Requires Bearer authentication.

get_content_standards

AdCP content-standards specialism. Retrieves the full details of a specific content standard, including all policies and their enforcement levels. Requires Bearer authentication.

list_content_standards

AdCP content-standards specialism. Lists content governance standards. When called with an 'account' object, returns buyer-defined standards stored for that brand. Without an account, returns the built-in catalog of VAST-relevant standards. Supports cursor-based pagination via the 'pagination' object. Requires Bearer authentication: Authorization: Bearer <api_key>.

update_content_standards

AdCP content-standards specialism. Updates the policies on an existing content standard set. The supplied policies array replaces the existing policy set. Requires Bearer authentication.

validate

validate_content_delivery

AdCP content-standards specialism. Validates that delivered creatives met the content standards. Accepts delivery records with creative references and returns per-record compliance status plus an overall summary. Requires Bearer authentication.

validate_vast

Validate a VAST XML tag against the IAB VAST 2.0-4.3 specification. Returns all issues found with severity, rule ID, location, and spec reference. A document is valid when errors == 0, regardless of warning or info count. Use wrapper_depth when validating a document inside a wrapper chain.

validate_vast_url

Fetch a VAST tag from a URL and validate it. Handles redirects. Use max_depth to control how deep wrapper chains are followed (default 5, per IAB VAST 4.x recommendation). AI agents typically receive VAST URLs rather than raw XML -- use this tool for that case.

adcp

get_adcp_capabilities

AdCP protocol discovery. Returns the AdCP version, supported protocols, and governance capabilities of this vastlint agent. Call this first when integrating vastlint into an AdCP creative pipeline — it declares which VAST creative features can be evaluated (spec compliance, HTTPS enforcement, wrapper depth). Part of the Ad Context Protocol (AdCP 3.0) specification.

calibrate

calibrate_content

AdCP content-standards specialism. Evaluates a creative artifact against a content standard set before delivery. Returns a per-policy verdict and an overall pass/fail result. Use this as a pre-flight check before launching a campaign. Requires Bearer authentication.

creatives

list_creatives

AdCP creative governance. Lists creatives known to this agent. For a validation-only agent like vastlint, this always returns an empty collection — creatives are validated on demand via validate_vast rather than stored. Requires Bearer authentication.

explain

explain_rule

Get full details for a specific VAST validation rule: description, spec reference, severity, what triggers it, and how to fix it. Use rule IDs from list_rules. This is the primary tool for understanding and fixing VAST issues flagged by validate_vast.

fix

fix_vast

Auto-fix a VAST XML tag. Applies all deterministic, safe fixes: HTTP → HTTPS upgrades in all URL-bearing elements, and removal of deprecated attributes. Returns the repaired XML, a list of every fix applied (rule ID + description + path), and any remaining issues that require manual intervention. Always re-validate the returned xml with validate_vast to confirm no errors remain.

rules

list_rules

List the full catalog of VAST validation rules available in vastlint. Returns rule IDs, default severities, and descriptions. Call this once and cache the result -- the catalog is static. Use rule IDs from this list with explain_rule for full details and fix guidance.

Endpoints

URL	Transport	State	Latency	Checked
https://vastlint.org/mcp	sse	answering	107 ms	8 min ago

VASTlint — questions

Answers built from our own checks of this server.

What can VASTlint do?

It exposes 14 tools, read directly from the server on our last check. Among them: calibrate_content, create_content_standards, delete_content_standards, explain_rule, fix_vast, get_adcp_capabilities and 8 more. The full list with descriptions is on this page — we take it from the server itself via tools/list, not from a README. How MCP servers expose tools in the first place →

What is VASTlint mostly used for?

Its tools cluster around content and validate. That is what this server is built to work with — the grouping comes from the actual tool names, not from a category we assigned.

Is VASTlint working right now?

We send a real MCP handshake every 15 minutes. Over the last 24 hours 91 of 91 checks got a reply (100.0%), average response time 118 ms. The bar chart above shows every period we have measured.

How do I connect VASTlint?

Copy the ready config from this page — we generate it for Claude Code, Claude Desktop, Codex, Cursor and VS Code, each with the file path that client actually reads. It is a remote server, so there is nothing to install — the client connects to the address.

Does VASTlint need an API key?

No. VASTlint completed a full MCP handshake with us as an anonymous client and listed its tools without asking for anything. All 14 of them are readable on this page. This is what we observed, not what the docs claim.

How fast is VASTlint?

It answers our handshake in 118 ms on average, which is faster than 80% of all working MCP servers we measure. That puts it in the quick quarter of the ecosystem. The comparison comes from our own checks across the whole registry, every 15 minutes.

Is VASTlint open source?

Yes — it is published under the NOASSERTION licence, written in Rust and 15 stars on GitHub. The source link is on this page, so you can read exactly what it does with your data before you connect it.