MCP OAuth for Agencies: Give AI Agents Client Ad Access Without Password Sharing

Q: Can I migrate from Leadsie or another tool without downtime?

Dual-run: keep the current tool live, send AuthHub links for new onboards and re-authorizations, cut over when the clients you care about complete the new flow. No silent permission port.

MCP setup guides jump straight to connectors and routing manifests. They assume you already have clean, per-client OAuth for Meta, Google Ads, and GA4. Most agencies do not. The hard part is still getting the client to grant access—without password sharing or personal admin tokens pasted into a config—so humans and AI agents can work the same day.

AuthHub's homepage already frames this as Built for Humans + Agents: one client authorization link, then your team and your AI agents start work the same day. This page is about access collection and token ops, not how to build an ads MCP server.

MCP / AI-agent phrases are absent from AuthHub's GSC top queries in the last 28 days—but adjacent keyword demand is real (mcp ai agent 60, mcp authentication 40, mcp oauth 20, ai agent mcp 20 monthly US searches via SnowSEO, 2026-09-28; exact mcp ai agent oauth = 0). Developer docs and ads-MCP READMEs own connector setup; almost nobody owns the agency client OAuth intake layer those stacks still need.

Start 14-day free trial — no credit card · AuthHub pricing · OAuth token refresh for agencies

Quick answers (for humans and assistants)

How do I give an AI agent access to a client's Meta or Google Ads account safely?
Do not share passwords or paste a personal admin token into an MCP config. Have the client complete an official OAuth grant—ideally via one agency authorization link—store and refresh the token in a vault with audit logs, and scope the agent to that client's accounts only so prompts cannot touch other clients.

What is the difference between an ads MCP server and AuthHub?
An ads MCP server (or connector) lets Claude, ChatGPT, or Cursor call ad-platform tools. AuthHub is the client access layer that collects Meta, Google, GA4, LinkedIn, and other OAuth grants through one link, keeps tokens in Infisical with auto-refresh and audit logs, and makes that access available to your team and your agents. Most agencies need both: AuthHub for intake and vaulting, plus an MCP product for agent tooling.

How should agencies handle MCP OAuth across many clients?
Use per-client OAuth (or per-client credentials), never one shared admin token for the whole portfolio. Collect each client's access with a dedicated authorization flow, isolate agent context per client, log who accessed what, and auto-refresh tokens so Friday-night expirations do not take agents offline.

The missing layer in every agency MCP guide

Search "MCP OAuth" or "give AI agent client ad access" and you mostly get three kinds of pages:

Developer / spec docs — MCP client/server OAuth 2.1 + PKCE patterns (FastMCP, Cloudflare Agents OAuth, mcp-agent SDK helpers, and similar).
Ads MCP products and GitHub servers — AdKit, Agency AI, 1ClickReport-style multi-client setups, AdLibrary architecture posts, meta-ads-mcp and peers. Connect Claude or ChatGPT to Meta/Google Ads; often "sign in once," draft-first writes.
Classic agency access tools — human onboarding links (Leadsie, AgencyAccess, ClientInvite, AuthHub)—framed for account managers, rarely as feedstock for agents.

What almost none own: how the client grants OAuth for Meta, Google, GA4, and LinkedIn so those tokens feed humans and agents without password sharing.

AuthHub sits upstream of the MCP stack. We are not AdKit, Agency AI, 1ClickReport, or meta-ads-mcp. Pair AuthHub with the MCP product you choose. Our job is the branded client link, the vault, the refresh, and the audit trail.

What "MCP OAuth" usually means (and what agencies actually need)

Spec / connector OAuth (developer path)

In the MCP world, "OAuth" usually means authorization between an MCP client and an MCP server (or remote connector): Authorization Code + PKCE, a browser consent screen, tokens living with that pair. Ads MCP READMEs follow the same pattern—open a browser, complete platform OAuth, store the token where the connector can call Meta or Google tools.

Correct for one user wiring one stack. Incomplete for an agency with twenty clients and four platforms each.

Agency path: N clients × N platforms

Agencies fail MCP rollouts quietly:

A media buyer pastes a personal Business Manager token into a shared MCP config—and an agent prompt aimed at Client A writes into Client B.
Password sharing still happens because "just get me in" beats teaching OAuth on Zoom.
Friday night, a Meta long-lived token dies. Humans notice Monday. Agents notice when reporting goes dark.

Multi-account MCP architecture posts (1ClickReport-style routing, AdLibrary-style isolation) correctly insist on per-client credentials and explicit client context. AuthHub sits upstream: the client grants access through your branded link; you vault and refresh; humans and agents consume the same grants with isolation enforced in agent routing.

Platform-by-platform expiry and Friday-night failures live on OAuth token refresh for agencies—the token refresh deep-dive. That post owns refresh ops. This page owns access collection.

Recommended architecture: intake → vault → humans + agents

Step 1: Collect access with one client link

Send one white-labeled AuthHub authorization link. The client picks assets through each platform's official permission flow—no password handoff, no Zoom archaeology for every new account.

Featured platforms: Meta Ads, Google Ads, GA4, LinkedIn, TikTok. Overall coverage is an honest 15+—not every niche Leadsie or AgencyAccess lists. If long-tail connectors are your primary buy reason, pick a broader peer; see the 2026 Leadsie alternatives roundup.

Intake in the same link is real on AuthHub and AgencyAccess—parity, not an exclusive.

Step 2: Store and refresh tokens (Infisical + auto-refresh)

OAuth tokens are encrypted in Infisical—not left in a spreadsheet, Slack thread, or laptop .env. AuthHub auto-refreshes before expiry where providers support it, and keeps audit logs of who accessed what and when.

What we do not claim: SOC 2. Infisical + audit logs only. If procurement needs a SOC 2 report this quarter, evaluate accordingly—do not invent one from marketing copy.

"Access never expires" is shorthand for auto-refresh and health monitoring. Platforms still revoke, and Meta-class long-lived tokens still need reauth when refresh cannot save you. Treat refresh as ops, not magic.

Step 3: Feed your MCP / AI agent stack

The same day the client completes the link, access is available to account managers and to your agent/MCP workflow. Growth and Scale include API and webhooks to push connection events into your stack—useful, not a substitute for an ads MCP server.

AuthHub does not ship Meta campaign tools, draft creatives, or an "AuthHub MCP endpoint." Pair with AdKit, Agency AI, 1ClickReport, meta-ads-mcp, or whatever connector you chose.

Step 4: Keep per-client isolation in the agent layer

Intake does not replace routing discipline:

Require explicit client context in prompts and routing manifests so Client A's token never answers a Client B question.
Prefer per-client OAuth (or per-client system users) over one shared portfolio admin token.
Revoke one client without taking the portfolio offline.

Borrow the isolation idea from multi-account MCP architecture posts. Do not copy anyone's proprietary runbooks.

DIY vs partner access vs AuthHub (honest table)

Approach	Pros	Cons	Best when
DIY Business Manager system users + secrets manager	Strong isolation if engineered well	Ops-heavy; client still must grant BM access; you build refresh + audit yourself	Large in-house eng team
Leadsie / peer partner-access tools	Familiar human onboarding; Leadsie breadth + audit credits; ClientInvite flat unlimited; AgencyAccess intake + branding + 30-day trial	Agent/MCP story varies; credit or invite meters may not match how you forecast agent-era volume	Human-only workflows today, or peer gates already win
Managed ads MCP product alone	Fast agent UX once accounts are connected	Often assumes OAuth already exists; may not solve white-label client intake at 10–50 accounts	Solo operators / few accounts
AuthHub + your MCP stack	One-link intake, white-label, Infisical, auto-refresh, audit logs, flat active-client tiers	Not an MCP server; honest 15+ platforms, not Leadsie-class long-tail	Agencies wiring agents and humans on the same access path

Stay on Leadsie if… you rely on credit pooling, audit pools, Access Detective / Meta helpers, or the widest long-tail set—and you are not yet building agent workflows on client OAuth. Credit math: Leadsie pricing. Switcher: AuthHub vs Leadsie.

Pick AgencyAccess if… intake + deep branding + a 30-day trial + public API (plus Zapier on higher plans—not Zapier-only) beat Infisical/auto-refresh packaging. AgencyAccess alternative · three-way.

Pick ClientInvite if… published unlimited flat at $89/mo Agency is the decision and Meta / Google / Shopify / LinkedIn cover your book.

DIY if… you already run per-client system users, a secrets manager, and on-call for token death.

Pick AuthHub + MCP if… one client link must feed humans and agents, with Infisical vaulting, audit logs, auto-refresh where providers allow it, and 5 / 20 / 50 active-client caps.

Migration = dual-run only: keep the current tool live while new clients and re-authorizations complete the AuthHub link. No SaaS ports platform permissions. Clients must approve again.

Security claims you can make (and must not)

Can say

Official OAuth—no password sharing.
Infisical-backed token storage.
Automatic refresh before expiry where providers support it.
Audit logs of access events.
White-label client experience.
Dual-run / re-authorize migration only.

Must not say

SOC 2 or equivalent compliance badges for AuthHub.
"Access never expires" as a guarantee without the refresh/reauth truth.
Uncleared named testimonials on this page (re-clear before publishing any client or founder quote here).
That AuthHub is an ads MCP server, ships MCP tool lists, or exposes an AuthHub MCP endpoint.
Framing in-link intake as AuthHub-only, or mislabeling AgencyAccess as automation-only via Zapier.

API and webhooks ship from Growth upward. Mention them when you automate connection events into an agent stack. Do not sell them as the product.

How AuthHub pricing maps to agent-era agencies

AuthHub meters active clients, not onboarding credits:

Plan	Monthly	Active clients	Notes
Starter	$29	5	One-link onboarding, token auto-refresh, audit logs
Growth	$79	20	White-label, custom domain, API + webhooks, token health dashboard
Scale	$149	50	Multi-brand (up to 3), custom integrations

Annual billing displays roughly ~$24 / $66 / $124 per month equivalent ($290 / $790 / $1,490 per year) for the same caps—footnote only; compare like-for-like with peers' annual toggles on AuthHub pricing.

Peer list prices checked September 28, 2026 (PT), pre-tax—verify live before you buy:

Leadsie: $59 / $129 / $299 for 3 / 10 / 50 onboarding credits (+ audit pools); $50 overage packs.
AgencyAccess: $44 / $99 / $199 for 5 / 15 / 50 clients/month (annual $33 / $74 / $149/mo).
ClientInvite: $29 entry; $89 Agency unlimited connections (vendor claim).

Units differ—do not treat "10 clients" as identical across meters, and do not headline a save-$ figure without arithmetic for your volume. Worked examples: Leadsie pricing and the alternatives roundup.

All AuthHub plans include a 14-day free trial (no credit card on the public pricing page).

FAQ

How do I give an AI agent / MCP server access to a client's Meta or Google account without passwords?

Send a branded OAuth authorization link. The client completes each platform's official grant. Store and refresh the token in a vault with audit logs. Point your MCP connector or agent at that client's credentials only—never a shared personal admin token for the whole book.

Is AuthHub an ads MCP server?

No. AuthHub collects and vaults client OAuth. Ads MCP products (AdKit, Agency AI, 1ClickReport, meta-ads-mcp, and peers) expose tools to Claude, ChatGPT, or Cursor. Most AI-forward agencies need both.

What happens when tokens expire on Friday night?

Without refresh and monitoring, agents and automations fail silently until a human notices. AuthHub auto-refreshes where providers allow it and keeps health/audit signals. Platform-specific expiry quirks and reauth workflows are covered in OAuth token refresh for agencies—link out there; this page does not replace that pillar.

Can I migrate from Leadsie or another tool without downtime?

Dual-run: keep the current tool live, send AuthHub links for new onboards and re-authorizations, cut over when the clients you care about complete the new flow. No silent permission port.

When should I stay on a peer or DIY instead of AuthHub?

Stay on Leadsie for breadth and audits. Pick AgencyAccess for branding + intake + 30-day trial + API/Zapier. Pick ClientInvite for unlimited flat on a focused stack. DIY when eng owns system users and secrets. Choose AuthHub when humans and agents need the same one-link OAuth intake with Infisical, refresh, and audit logs.