01 Prospeo Lookalike

Prospeo Lookalike - Seed-Based Company Discovery

Turn seed companies (domains, an ICP description, or "similar to X") into similar companies via Prospeo's company_lookalike filter (33-filter, 30M+ company database). Two ways to finish:

• Mode 1 - Lookalike list (headline): return the actual similar companies, ranked by similarity

tier. The lookalike filter runs alone - no ICP stacking - so you get a full list, not single digits.

• Mode 2 - Seed → ICP handoff: analyze the 25 closest matches for patterns, build an ICP, and hand

it to [01-prospeo-discover](../01-prospeo-discover/SKILL.md) for a broad firmographic search.

Discovery (skill 01) deliberately treats lookalike as a throwaway pattern-finder and drops it before its real search. This skill is the opposite - here the lookalike matches are a first-class deliverable.

Your job

1. Collect the seed(s) - domains, named companies, or an ICP paragraph - and pick the mode.
2. Resolve seeds to what the API needs (domain string, company IDs, or icp_text).
3. Run the lookalike search, present the ranked matches with the similarity tier.
4. Offer the next step: export the list (Mode 1) or build an ICP and route to discovery (Mode 2).

Credits are real money: each search page costs 1 credit; account and suggestion calls are free. Guard spend, especially on export.

Setup

Auth reads from environment variables. Nothing is hardcoded.

• PROSPEO_API_KEY - required for every Prospeo call.
• Google Sheets export reads OAuth credentials from GOOGLE_TOKEN_PATH (default ~/.google/token.json).

Only needed when exporting.

The curl examples use $PROSPEO_API_KEY as the key.

API basics

Base URL: https://api.prospeo.io
Auth header: X-KEY: $PROSPEO_API_KEY
Content-Type: application/json

Three endpoints:

• GET /account-information - plan and credit balance (free)
• POST /search-company - the search, incl. lookalike (1 credit per page)
• POST /search-suggestions - resolve locations, technologies, industries, other open-ended values (free)

The one body-shape rule that breaks searches when you get it wrong: filters go inside a "filters": {} wrapper, and "page" is a sibling of "filters", not inside it.

curl -s -X POST "https://api.prospeo.io/search-company" \
  -H "X-KEY: $PROSPEO_API_KEY" -H "Content-Type: application/json" \
  -d '{"filters": {"company_lookalike": { ... }}, "page": 1}'

Full curl formats, the search-suggestions key table, and the formats to avoid live in references/api-curl.md - read it before resolving values for the first time in a session.

Step 0 - Plan and enum check (internal, run once)

Do this silently before prompting the user. Don't narrate it or show step numbers.

Plan and credits. Call GET /account-information and read current_plan and remaining_credits from the response object. Store them.

Lookalike needs Starter or higher. company_lookalike is filter #22, gated to Starter+ (see references/plan-filter-map.md). On the Free plan it is unavailable - if the account is Free, say so up front and stop, rather than assembling a search that will fail:

> Lookalike needs a Starter plan or higher; this account is on Free. I can still build a list from an ICP > description with 01-prospeo-discover instead.

If remaining_credits is under 10, tell the user their balance and that each page costs 1 credit before spending anything.

Enum cache. Read references/prospeo-enums.json and check last_updated. If it's missing or older than 21 days, refresh it with references/enum-refresh.md; otherwise use the cached values. You only need enums when the user layers ICP constraints (industry, size, etc.) onto the lookalike or when you build the Mode 2 ICP. Technologies (4,946) and locations resolve at runtime via search-suggestions.

Then present a clean prompt and wait for input.

Prospeo Lookalike ready.
Plan: {plan} | Credits: {credits}

Give me the seed companies you want to find matches for - domains, names, or a short
description of the ideal company.

Step 1 - Collect seeds and resolve them

The lookalike filter takes exactly ONE mode per call. Pick by what the user gave you:

| What the user gave | Mode | How to build it | |---|---|---| | One domain ("similar to hubspot.com") | domain | {"domain": "hubspot.com"} - no lookup needed | | Multiple domains / named companies | companyoids | Resolve each to a Prospeo company ID first, then {"company_oids": [...]} | | A paragraph describing the ideal company | icptext | {"icp_text": "..."} (max 5,000 chars) - no lookup needed |

Resolving multiple domains to company IDs (1 credit each): search company.websites.include for each domain, read the company ID off the result, collect the IDs. Full detail and the exact response field to read live in references/lookalike-modes.md. A single domain skips this - use domain mode directly.

Similarity tier controls how close the matches are:

• "T1" - most similar (tightest, fewest results)
• "T2" - balanced (a good default for a usable list)
• "T3" - broadest (default if unset)

match_all only applies to multi-seed (company_oids) searches: false (default) = union of each seed's lookalikes; true = intersection (companies similar to all seeds at once - much narrower).

Confirm the assembled lookalike filter with the user before spending a credit:

> Seeds: torc.ai, field.ai (resolved to 2 company IDs) > Tier: T2 (balanced) | match_all: false (union) > This runs the lookalike search - 1 credit for page 1. Go?

Worked plain-English → lookalike JSON examples are in references/mapping-examples.md.

Step 2 - Pick the mode with the user

Once seeds are ready, ask which outcome they want (or infer it from how they framed the request):

• "Just give me the similar companies" / a competitor or customer list to expand → Mode 1.
• "Use these to figure out who to target" / closed-won logos → Mode 2 (the pattern → ICP handoff).

If unsure, default to Mode 1 (the direct answer to "find similar companies") and offer Mode 2 as a follow-up. The two aren't exclusive - you can show the Mode 1 list and offer to distil an ICP from it.

Step 3a - Mode 1: lookalike list

Run POST /search-company with company_lookalike as the only filter (optionally plus a light location or size constraint the user explicitly asked for - but never a full ICP stack, which collapses the count). Fetch page 1, present:

Found {total_count} companies similar to {seeds} (tier {tier}).

Preview (top 25, most similar first):
| # | Company | Domain | Industry | Employees | Location | Revenue | Funding |
|---|---------|--------|----------|-----------|----------|---------|---------|
| 1 | ...     | ...    | ...      | ...       | ...      | ...     | ...     |

Credits used: 1 | Full export: {total_pages} credits | Balance: {credits - 1}

Next steps:
1. Export the full list
2. Tighten the tier (T1 for closer matches) or add a location/size constraint
3. Build an ICP from these patterns instead (Mode 2)

If total_count is over 2,000, suggest tightening the tier before a full export. If it's under 10, suggest loosening the tier (T3) or dropping any extra constraint you stacked on.

Step 3b - Mode 2: seed → ICP handoff

Use the lookalike matches to build an ICP, then route to discovery for the broad search.

1. Fetch page 1 only (25 results, 1 credit). The response already carries industry, headcount, location,

funding, revenue, and keywords - no export needed to analyze.

1. Read the 25 for patterns across the mandatory ICP filters: dominant industries, typical size, location

concentration, funding stages, common keywords.

1. Present the pattern-built ICP and let the user confirm or adjust.
2. Run the confirmed ICP as a firmographic search - without any company_lookalike filter (stacking it

with a full ICP collapses the count). It's the same POST /search-company call, just with ICP filters; assemble it from references/filters-full.md and export with the script below (it accepts a plain ICP filter set too - see its note). Say why once:

> These 25 are the closest matches; the ICP I pulled from them (industry, size, geo, funding) will give > you a much fuller list than the lookalike filter alone.

1. Watch for broad-industry overshoot - re-inject the keyword signal. When the seeds live in a niche

(robotics, autonomy, biotech) but classify under a huge parent industry like Software Development, an ICP of industry + size + geo alone can balloon into six figures - the specificity that made the lookalikes good lived in the keywords, and a plain firmographic ICP drops it. Before handing off, sanity-check the count on page 1: if it's implausibly large (tens of thousands), add the 1-2 dominant recurring keywords from step 2 as a company_keywords constraint, or drop the broad parent industry and keep only the niche one. Real example: robotics seeds → Software Development + Robotics Engineering in US/Canada returned ~138K; Robotics Engineering alone cut it to ~980, and + keyword "robotics" landed ~1,491 - both campaign-usable. A count in the low thousands is the target; low six figures means the keyword signal got lost.

> Related skill (optional): if [01-prospeo-discover](../01-prospeo-discover/SKILL.md) is installed, you can > hand it the confirmed ICP instead of running the search here - it adds mandatory-filter defaults and > optional-filter recommendations. An option, not a prerequisite; this skill runs the ICP on its own.

Step 4 - Export (only when asked)

Export uses the Python script, which paginates the search and writes the chain run folder. Don't paginate the API by hand for exports.

Script: scripts/sheets_export.py · Deps: pip install -r ../_shared/requirements.txt (only the opt-in Sheets export needs the gspread/google-auth extras in that file)

# Preview count without spending export credits
python3 scripts/sheets_export.py --filters lookalike_filters.json --dry-run

# Standard chain export - writes runs// (records.jsonl + tracker + meta)
python3 scripts/sheets_export.py --filters lookalike_filters.json

# Also export to Google Sheets (new spreadsheet, or an existing one)
python3 scripts/sheets_export.py --filters lookalike_filters.json --sheets
python3 scripts/sheets_export.py --filters lookalike_filters.json --spreadsheet-id SHEET_ID --tab-name "lookalikes"

# Cap pages for very large result sets
python3 scripts/sheets_export.py --filters lookalike_filters.json --max-pages 20

Save the current filter JSON (the company_lookalike block wrapped as {"company_lookalike": {...}}, plus any extra constraint) to the path you pass in --filters, then run the script. The Google Sheets export is opt-in (--sheets, or implied by --spreadsheet-id/--tab-name); it writes a Results tab (company data incl. similarity tier) and a Search Info tab (the seeds + tier). The chain never depends on the Sheet.

Before exporting, show the cost and confirm:

> Full export: {totalpages} pages = {totalpages} credits. Your balance: {credits}. Proceed?

The script also confirms before fetching more than 10 pages, and --dry-run previews the count for free.

Shared output (runs//)

Every export writes a run folder under this skill's runs/ per _shared/CONVENTIONS.md: records.jsonl (the file downstream skills consume), tracker.json, and meta.json (filters, seed provenance, credits). Records carry the stage-01 fields plus lookalike_tier, and the seed provenance in filters_matched so downstream skills know these came from a lookalike run:

{"company": "Aurora Innovation", "domain": "aurora.tech", "person": null, "industry": "Autonomous Vehicles", "size": "201-500", "location": "Pittsburgh, Pennsylvania, United States", "funding": {"stage": "Series C", "total": "820M", "last_date": "2025-06-14"}, "revenue": "", "keywords": ["autonomy", "trucking"], "lookalike_tier": "T2", "filters_matched": ["Lookalike: 2 seed company IDs | tier T2 | union"]}

Where this sits in the chain

• Step 01 (discovery layer). Sibling of [01-prospeo-discover](../01-prospeo-discover/SKILL.md)

(ICP-filter build) and 02-apify-maps-discover (local SMB). Use this one when the user starts from example companies; use discover when they start from filters.

• Mode 2 output feeds 01-prospeo-discover; Mode 1 output feeds the rest of the chain

(04 signals → 05 signal-builder → 06 resolution) via records.jsonl.

• The router ([00-gtm-router](../00-gtm-router/SKILL.md)) picks this skill when the ICP is defined by

seed logos rather than firmographic filters.

References

• references/lookalike-modes.md - the three lookalike modes in detail, oid resolution, tiers, pattern analysis
• references/mapping-examples.md - plain-English → lookalike filter JSON examples
• references/api-curl.md - exact curl formats, the full search-suggestions key table, formats to avoid
• references/filters-full.md - all 33 filters (for any ICP constraint you layer on or build in Mode 2)
• references/plan-filter-map.md - which filters each plan supports (lookalike = Starter+)
• references/enum-refresh.md - how to refresh the enum cache
• references/prospeo-enums.json - cached valid enum values

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: Zevenue
• Source: Zevenue/headless-gtm
• License: MIT
• Homepage: https://zevenue.com

Install and usage instructions live in the source repository linked above.