Surface undocumented filter params across four skills

[ZLeventer]

What does this PR do?

Adds valid but previously undocumented ZoomInfo API parameters to four existing skills. These parameters exist in the ZoomInfo API but were absent from the skill workflows, meaning users couldn't access them through natural language in Cowork.

Type of change

• Skill improvement (existing skill)

Skills affected

• skills/build-list/
• skills/enrich-contact/
• skills/enrich-company/
• skills/find-similar/

ZoomInfo tools used

No new tools — enhancements to existing tool usage patterns.

Changes per skill

build-list

• hasEmail: true — maps from natural language like "with verified email" or "has email"; narrows contact lists to records with email on file
• hasPhone: true — maps from "with direct phone" or "has phone"
• lastUpdatedDateAfter — maps from "updated in the last X months"; computed from today's date; ensures freshness on large lists
• metroArea — metro-precision geography filter (more precise than state alone); maps from "in the [city] area"
• fundingStage — maps from "Series B+", "recently funded", "post-Series A"; enables funding-stage-based prospecting
• List Summary now explicitly notes when these filters were applied

enrich-contact

• hasEmail: true added as a fallback search refinement when name+company returns too many results
• supplementalEmail added to output format (secondary email addresses)
• Stale-record flag: if lastUpdated > 12 months, surface a warning to re-verify before outreach

enrich-company

• metroArea added to fallback search when user provides a city or metro area for disambiguation
• fundingStage and metroArea added to Growth Signals output block

find-similar

• Documents a known limitation: find_similar_companies does not accept firmographic filters directly. Instructs Claude to apply geography/size/funding constraints as post-filters or cross-reference via search_companies.

Testing

Parameters validated against ZoomInfo API documentation. End-to-end Cowork testing pending credential access.

Entitlements required

None — all parameters are available on standard ZoomInfo API access.

Checklist

• Skill directory names unchanged
• No frontmatter modified
• Lookup-first pattern preserved in all modified skills
• Output format additions are additive (no breaking changes to existing output structure)