Paste one prompt into Claude with LeadOcean connected and get a sized list of agency founders before you spend a single record. Connect the server at https://api.leadocean.io/mcp first. Setup is on the MCP page.
The prompt
Find founders at marketing and advertising agencies in the United States.
1. Call leadocean_list_enum_values for industry and pick the marketing
and advertising agency values.
2. Call leadocean_count_leads with seniority founder, those industries
and country US.
3. Tell me the count and the filters you used.
4. Do not call leadocean_search_leads until I say go.What it resolves to
| Filter | Value |
|---|---|
| seniority | founder |
| industry | Advertising Services, Marketing Services, Marketing and Advertising |
| country | US |
seniority is finer than jobLevel and has 12 lowercase values, founder among them. "Agency" is not an industry value, so the prompt maps it to the three marketing and advertising strings. Enum values are exact strings, which is why step 1 looks them up.
How many match
49,846 mailable people matched on 1 October 2026. Filters: seniority founder, industry Advertising Services, Marketing Services or Marketing and Advertising, country US.
Mailable means verified, catch_all_valid or catch_all, the count_leads default. The count is free. The facets show 30,828 of them sit at companies with 1-10 employees and 11,734 at 11-50. Most of this list is small, owner-run shops, so add employeeRange before you write copy. 3,794 sit at 51-200.
What you get back
Search rows carry the fields below. These are placeholder values, not real records.
| Title | Company size | Industry | Country |
|---|---|---|---|
| Founder | 1-10 | Advertising Services | US |
| Co-Founder and CEO | 11-50 | Marketing Services | US |
| Founder | 51-200 | Marketing and Advertising | US |
Variations
- Add "only companies with employeeRange 11-50 and 51-200" to skip solo operators.
- Swap seniority founder for "jobLevel C-Team" to reach CEOs and COOs as well.
- Change country to GB and ask Claude to count again before searching. Each count is free, so compare the two totals first.
Records it spends
The count and enum lookups are free. leadocean_search_leads costs 1 record per person returned, so a limit of 25 costs 25 records. Free gives you 1,000 records one-off with no card. Pro is $499 a month. See pricing.
Related prompts
More prompts live in the prompts hub.
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