brand-voice: add Grain as a third meeting-intelligence source alongside Gong and Granola

[adams]

What this changes

Adds Grain (grain.com) as a sibling meeting-intelligence source alongside the existing Gong and Granola integrations in partner-built/brand-voice/.

Files touched

File	Change
partner-built/brand-voice/.mcp.json	Add grain server block (URL: https://api.grain.com/_/mcp)
partner-built/brand-voice/skills/discover-brand/SKILL.md	Add Grain to platform enumerations in skill description, enabled-platforms list, supplementary-platforms list, error messages, and confirmation prompts
partner-built/brand-voice/skills/guideline-generation/SKILL.md	Add Grain to conversation-transcripts source list
partner-built/brand-voice/agents/discover-brand.md	Add Grain per-platform block in Phase 1 Broad Discovery, mirroring existing Granola block; update Quality Standards supplementary-platforms list
partner-built/brand-voice/agents/conversation-analysis.md	Add Grain to transcript sources list and tools-not-restricted comment
partner-built/brand-voice/commands/discover-brand.md	Add Grain to skill description and platform-validation messages
partner-built/brand-voice/commands/generate-guidelines.md	Add Grain to connected-platforms list and supported-transcript-sources line
partner-built/brand-voice/skills/discover-brand/references/search-strategies.md	Add new ## Grain (Meeting Intelligence) section with query patterns and tips, mirroring the existing Granola section; add Grain step to Maximizing Coverage numbered list

What stays the same

• No changes to the discovery 4-phase algorithm
• No changes to conversation-analysis agent task logic, output format, or quality standards
• No changes to guideline-generation synthesis or save flow
• No changes to source-ranking weights or triage tiers
• Plugin works identically for users who don't connect Grain

Why this matters

brand-voice's flagship use case — synthesizing a brand style guide from existing conversational and document corpora — only works for users whose meeting transcripts are accessible to the plugin. Gong and Granola cover the enterprise-rep and broad-AI-notepad segments. Grain covers the SMB / mid-market sales and product-team customer-research segment. Today those users install brand-voice and the conversation-pattern discovery sits dark for their meeting corpus.

Background on Grain

We've been studying brand-voice as the architectural mirror for a Grain-published plugin we're shipping (Cowork partner-built, in design as of late May). Reciprocal opportunity: brand-voice's discover-brand and conversation-analysis already pull transcripts from Gong and Granola; Grain is a sibling option in the same category and slots in alongside them. Grain's MCP launched June 2025 — reference: https://grain.com/release-note/06-18-2025 and https://developers.grain.com.

Anticipated reviewer questions

• Is the Grain MCP stable? Yes, public, documented at developers.grain.com, used in production by Grain customers and Grain's own internal automation.
• Why a full reference-doc section vs. just adding Grain to the platform enumeration? To match the depth of the existing Gong and Granola sections in search-strategies.md. Without it, the cross-platform tips guidance would skip Grain.
• Does this overlap with the Grain-published plugin you mentioned? No — that's a complementary user-facing plugin. This change makes brand-voice's existing discovery work for Grain users; the user-facing Grain plugin gives Grain users their own AI-powered workflows. The two don't compete on surface or capability.

cc Tribe AI maintainers — happy to iterate on scope or align with any partner-built convention you'd prefer.

— Mike Adams, Founder/Chairman, Grain