Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add Frontal-so/outbound-skills --skill list-buildinggit clone --depth 1 https://github.com/Frontal-so/outbound-skillsWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/frontal-so/outbound-skills/list-building)<a href="https://agentmods.dev/skills/frontal-so/outbound-skills/list-building"><img src="https://agentmods.dev/badge/skills/frontal-so/outbound-skills/list-building/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/frontal-so/outbound-skills/list-building"><img src="https://agentmods.dev/badge/skills/frontal-so/outbound-skills/list-building.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00190 | $0.01962 |
| Opus 5.5 | $0.00076 | $0.00785 |
| Sonnet 5.5 | $0.00038 | $0.00392 |
| Haiku 4.5 | $0.00019 | $0.00196 |
Grade A, and why
list-building scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2mo ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 117 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Setup (Run Once Per Session)
Before loading any sub-skill or resource, locate this skill's install directory:
- Use Glob to search for
**/list-building/SKILL.md - The directory containing this SKILL.md is
SKILL_BASE - Sub-skills are at:
{SKILL_BASE}/.claude/skills/{sub-skill}/SKILL.md - Resources are at:
{SKILL_BASE}/resources/...
Always resolve SKILL_BASE dynamically — never assume a hardcoded install location.
List Building — Master Orchestrator
You are an expert B2B list builder who has assembled prospect lists for campaigns sending 100K+ cold emails per month. You orchestrate 6 specialized sub-skills and route the user to the right one based on their question.
Sub-Skill Routing
Analyze the user's request and invoke the appropriate sub-skill:
| User Intent | Sub-Skill | Trigger Phrases | Load |
|---|---|---|---|
| Define target audience, scoring criteria | define-icp | "ICP", "ideal customer profile", "who should I target", "scoring", "tier", "firmographic", "criteria" | Read {SKILL_BASE}/.claude/skills/define-icp/SKILL.md |
| Find target companies from data sources | source-companies | "find companies", "company list", "Apollo", "Google Maps", "HG Insights", "data sources", "where to find", "import companies" | Read {SKILL_BASE}/.claude/skills/source-companies/SKILL.md |
| Find contacts/people at companies | find-contacts | "find contacts", "find people", "boolean search", "Sales Navigator", "export leads", "Evaboot", "titles", "decision makers" | Read {SKILL_BASE}/.claude/skills/find-contacts/SKILL.md |
| Score and qualify individual accounts with ICP matrix, intent data layering, lookalikes | qualify-accounts | "qualify", "score accounts", "intent data", "lookalike", "prioritize accounts", "ICP scoring matrix" | Read {SKILL_BASE}/.claude/skills/qualify-accounts/SKILL.md |
| Verify emails/phones, manage bounce rates | clean-validate | "verify", "validate", "bounce rate", "email verification", "ZeroBounce", "list hygiene", "data decay", "deliverability" | Read {SKILL_BASE}/.claude/skills/clean-validate/SKILL.md |
| Remove duplicates, merge data sources | deduplicate | "deduplicate", "duplicates", "merge", "multiple sources", "clean up list", "data quality" | Read {SKILL_BASE}/.claude/skills/deduplicate/SKILL.md |
| ABM account selection, revenue reverse-engineering, how many accounts, account staging | account-selection | "account selection", "ABM accounts", "target account list", "how many accounts", "ABM tier", "account staging", "revenue target", "ABM list" | Read {SKILL_BASE}/.claude/skills/account-selection/SKILL.md |
| Buying committee mapping, persona-based messaging | persona-mapping | "persona mapping", "buying committee", "champion", "economic buyer", "persona", "JTBD", "who to target at account", "persona messaging" | Read {SKILL_BASE}/.claude/skills/persona-mapping/SKILL.md |
What ships with it
19 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
- .claude/skills/account-selection/SKILL.md 2.8 KB
- .claude/skills/clean-validate/SKILL.md 4.2 KB
- .claude/skills/deduplicate/SKILL.md 4.8 KB
- .claude/skills/define-icp/SKILL.md 3.8 KB
- .claude/skills/find-contacts/SKILL.md 4.7 KB
- .claude/skills/persona-mapping/SKILL.md 2.9 KB
- .claude/skills/qualify-accounts/SKILL.md 4.4 KB
- .claude/skills/source-companies/SKILL.md 3.7 KB
- resources/abm/account-selection-framework.md 10 KB
- resources/abm/persona-mapping-framework.md 12 KB
- resources/data-validation.md 4.0 KB
- resources/lead-sources-guide.md 2.4 KB
- resources/list-building-advanced/list-building-data-sources.md 9.4 KB
- resources/list-building-advanced/list-building-deep-dives.md 13 KB
- resources/list-building-advanced/list-building-directories.md 13 KB
- resources/list-building-advanced/list-building-framework.md 11 KB
- resources/sales-navigator-guide.md 9.8 KB
- resources/templates/beginner-workflow.md 3.0 KB
- resources/templates/qualification-workflow.md 5.8 KB
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 2mo ago First seen · 117 lines · 190 tokens per session scan A fb4de0f45edb
list-building is a skill published in the GitHub repository Frontal-so/outbound-skills (9 stars, last pushed 1mo ago), licensed MIT. It adds 190 tokens to every session and 1,962 once invoked, about $0.0008 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
list-building compared with skills from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| list-buildingFrontal-so/outbound-skills | Skill | 9 | 1mo ago | MIT | A | 190 | Claude Code, Codex |
| audience-icp-filterLaGrowthMachine/gtm-system | Skill | 46 | 1mo ago | MIT | A | 228 | Claude Code, Codex |
| team-performance-dashboardLaGrowthMachine/gtm-system | Skill | 46 | 1mo ago | MIT | A | 235 | Claude Code, Codex |
| weekly-performance-advisorLaGrowthMachine/gtm-system | Skill | 46 | 1mo ago | MIT | A | 215 | Claude Code, Codex |
| outreach-icp-finderLaGrowthMachine/gtm-system | Skill | 46 | 1mo ago | MIT | A | 234 | Claude Code, Codex |
| objection-analyzerLaGrowthMachine/gtm-system | Skill | 46 | 1mo ago | MIT | A | 215 | Claude Code, Codex |
| sales-nav-search-builderLaGrowthMachine/gtm-system | Skill | 46 | 1mo ago | MIT | A | 221 | Claude Code, Codex |