Add https://api.leadocean.io/mcp as a custom connector in Claude, sign in with OAuth, and Claude can count, search and enrich people and companies. No API key is pasted anywhere. The free plan gets the same server as Pro.
This page covers Claude (claude.ai and Claude Desktop). For the terminal client, see Claude Code. Other clients are on the MCP hub.
Before you start
You need a LeadOcean account and a Claude account. Create a free LeadOcean account. It has no card and 1,000 records, one-off, and it needs a work email.
The Claude custom connector docs, September 2026, say custom connectors are available on Free, Pro, Max, Team and Enterprise plans. Free Claude users are limited to one custom connector. On Team plans only Owners and Primary Owners can add one. On Enterprise, Owners, Primary Owners and custom roles with Manage access to Libraries can.
Add the server
Claude connects from Anthropic's cloud, not from your laptop. The LeadOcean server is public, so that works without a firewall change. On Pro and Max, per the Claude docs:
- Go to Customize, then Connectors.
- Click "+ Add", then "Add custom connector".
- Enter a name, such as
LeadOcean. - Paste the URL
https://api.leadocean.io/mcpand click "Continue". - Review the authentication settings Claude detected, then click "Continue".
- Choose how people connect, then click "Add".
Team and Enterprise owners start at Organization settings, then Connectors, then "Add", then "Custom", then "Web". Members then open Customize, then Connectors, and click "Connect".
The Claude docs do not say which "OAuth client" option to pick for a given server. The default is "Use Claude's published identity (Recommended)". LeadOcean's OAuth server also supports dynamic client registration, so "Register automatically" is the fallback if the default is refused.
Leave "Request headers" empty. You do not need one.
Sign in
Sign-in is OAuth 2.1 in your browser. Pick "Sign in now", or choose "Sign in when needed" and Claude asks the first time a tool runs. A LeadOcean page opens. Sign in, approve, and you return to Claude.
Claude never sees your password, and there is no key to paste. LeadOcean supports dynamic client registration at https://api.leadocean.io/oauth/register (scope mcp), so Claude can register itself.
Turn the connector on per chat: click "+" at the lower left of the chat box, then "Connectors", and switch LeadOcean on. Claude asks before it runs a tool. Click "Allow always" only for tools you trust to run unsupervised.
To revoke, disconnect or remove the connector in Customize, then Connectors. You can also remove the app under API keys, Connected apps in your LeadOcean account.
Your first prompt
Start with a count. Counting is free.
How many VP-level sales leaders in Germany can I email? Count only. Do not pull anyone.
Claude calls leadocean_count_leads with jobLevel set to VP, jobFunction set to Sales & Business Development and country set to DE. That costs 0 records. We ran the same filters on 2026-10-01 and the tool returned 1,128, an exact total.
That figure covers people whose email status is verified, catch_all_valid or catch_all, the tool's default. It is not everyone we hold for those filters.
When the count looks right, ask: "Pull five of them with title and company." That calls leadocean_search_leads and costs 1 record per person returned, so 5. For more prompts to copy, see enrich leads with prompts and use Claude for recruiting.
The 12 tools
Claude lists them as leadocean_ plus the name below. Six of them spend no records.
| Tool | What it does | Records |
|---|---|---|
leadocean_count_leads | Counts people for a filter set. | Free |
leadocean_list_filters | Lists valid filters and enum values. | Free |
leadocean_list_enum_values | Looks up exact strings, such as one of 534 industries. | Free |
leadocean_get_account | Shows plan, records left and export ceilings. | Free |
leadocean_get_export | Polls one export for status and download link. | Free |
leadocean_list_exports | Lists your exports. | Free |
leadocean_search_leads | Finds people by title, level, country, domain and more. | 1 per person returned |
leadocean_get_lead | Enriches one person by LinkedIn URL, email or person_id. | 1 |
leadocean_find_phone | Returns the phone numbers held for one person. | 1 |
leadocean_get_company | Enriches one company by domain or LinkedIn URL. | 1 |
leadocean_search_companies | Finds companies by industry, size, funding or technology. | 1 per company returned |
leadocean_export_leads | Starts a bulk CSV export of people. | 1 per row |
A leadocean_get_lead call that finds nobody costs nothing. Exports reserve up to your limit when they start, so count first. Source: LeadOcean MCP docs, September 2026.
Troubleshooting
| Symptom | Cause | Fix |
|---|---|---|
| Claude cannot reach the server | A typo in the URL, or your organization blocks custom connectors. Claude connects from Anthropic's cloud, so your own network is not the path. | Re-check https://api.leadocean.io/mcp. Claude docs say to remove and re-add a connector to edit it. On Team or Enterprise, ask an Owner. |
| Connector shows but tools do not appear | OAuth window was closed before you approved, or the connector is off in this chat. | Click "Connect" again and approve. Then switch LeadOcean on under "+", then "Connectors". |
| Sign-in is refused | The OAuth client option was rejected. | Remove the connector, add it again, and set OAuth client to "Register automatically". |
| 402 | Your 1,000 free records are spent, or an export needs more than you have left. The free plan is one-off. | Ask Claude to run leadocean_get_account. Move to Pro at $499 a month, or shrink the limit. |
| 429 | Past the rate limit of 100 requests per second per key, or an export ceiling was reached. | Wait a second and retry, or ask Claude to work in small batches. Export 429s return a reset time. |
| Wrong enum, filter rejected | A value is not in the catalogue, such as an invented industry. | Ask Claude to call leadocean_list_enum_values and use the exact string it returns. |
FAQ
Do I need an API key for Claude?
No. The MCP server uses OAuth sign-in. The REST API uses an x-api-key header. Both spend the same records from one balance.
Is the free plan the same server as Pro?
Yes. Free is 1,000 records, one-off, with search and enrich both available. Pro is $499 a month, flat, with no per-record price.
What does Claude cost me per prompt?
Only records it receives. Counts, filter lookups and account checks are free. Tell it a limit, such as "stop after 25 records", and it will hold to it.
Connect Claude to 693M people, free
Free to start. No credit card. 1,000 records to spend whenever you like.
Get your free API key →