Building Domain-Specific Plugins

Every industry has workflows that are unique to it. Legal firms have contract review cycles with jurisdiction-specific compliance checks. Healthcare organizations have clinical documentation workflows governed by HIPAA. Financial services firms have due diligence processes with regulatory requirements that change quarterly. Anthropic's default plugins cover the 80% of general business functions. The remaining 20% — the industry-specific procedures, the regulatory workflows, the domain terminology — is where custom domain plugins create outsized value.

Building a domain plugin starts with domain expertise. If you are in legal, the plugin needs to know the difference between a representation and a warranty. If you are in healthcare, it needs to understand the difference between a progress note and a discharge summary. If you are in finance, it needs to know that a 10-K and a 10-Q have different filing requirements. This domain knowledge is the moat — it is what makes a custom plugin dramatically more useful than prompting Claude with "you are a legal expert."

The construction process follows a specific pattern. First: document the domain vocabulary. Create a glossary of terms, abbreviations, and concepts that the plugin must understand. Second: document the workflows. What steps does a domain expert follow, in what order, with what decision points? Third: document the quality criteria. What does "good" look like in this domain? What are the common errors that a non-expert makes?

Feed all three — vocabulary, workflows, quality criteria — to the meta plugin. The vocabulary becomes contextual knowledge that the skills draw on. The workflows become structured procedures. The quality criteria become QA checklists. The result is a plugin that does not just know about the domain — it operates within the domain's standards and catches domain-specific errors.

Let me be direct about the limitation. A domain plugin built by a domain expert is powerful. A domain plugin built by someone guessing at domain knowledge is dangerous. If you are building a legal plugin and you are not a lawyer, partner with a lawyer. If you are building a healthcare plugin and you are not a clinician, partner with a clinician. The plugin amplifies whatever knowledge you encode — including wrong knowledge. Domain plugins are not a shortcut to domain expertise. They are a tool for scaling domain expertise that already exists.