Drug-Drug Interaction (ToolUniverse Claude Skill)

A ToolUniverse agent skill that evaluates a drug pair for interaction risk by reasoning through CYP metabolic pathways, transporter effects, and pharmacodynamic mechanisms, then grading the evidence and producing a clinical risk score.

   
Type Claude Skill (one of ToolUniverse’s pre-built agent skills)
Supplier Zitnik Lab, Harvard Medical School
Availability GA — part of the ToolUniverse skills collection (skills/tooluniverse-drug-drug-interaction/)
Pricing Free / OSS (Apache-2.0); reasoning runs locally, database calls go through the ToolUniverse MCP server
Capabilities Read-only — drives ToolUniverse tool calls; no data writes
Verified works · 2026-07-20
Security caution · 2026-07-20 — provenance/Apache-2.0 clear but ships a .env.template requesting user API keys for external DBs (BioGRID DisGeNET OMIM USPTO NVIDIA BRENDA)

How to install

This skill calls ToolUniverse tools, so the ToolUniverse MCP server must be installed first (see the ToolUniverse page). Simplest registration:

claude mcp add --transport stdio tooluniverse -- uvx tooluniverse

Then add the skills:

  • Claude Code — install the whole skill collection (the skill resolves as tooluniverse-drug-drug-interaction): 
    npx skills add mims-harvard/ToolUniverse
  • Manual / other agents — copy just this skill directory into your skills folder: 
    git clone https://github.com/mims-harvard/ToolUniverse
cp -r ToolUniverse/skills/tooluniverse-drug-drug-interaction ~/.claude/skills/

The skill sets disable-model-invocation: true upstream, so invoke it explicitly (e.g. ask Claude to “use the drug-drug-interaction skill”) rather than relying on automatic dispatch.

What it does

Runs a structured interaction assessment that combines local pharmacology reference data with live database queries:

  • Pharmacokinetic analysis — ChEMBL_get_drug_mechanisms (substrate/inhibitor/inducer classification), KEGG_get_drug (metabolic pathways), and drugbank_get_drug_interactions_by_drug_name_or_id (P-gp/OATP/OAT/OCT transporter effects). A local scripts/pharmacology_ref.py is consulted first for instant CYP/UGT enzyme roles and known critical interactions.
  • Pharmacodynamic analysis — identifies receptor overlap and shared organ-toxicity pathways.
  • Evidence grading — DailyMed_get_spl_by_setid (FDA label warnings) and PubMed_search_articles (clinical evidence), graded FDA label > clinical study > theoretical.
  • Risk scoring — combines mechanism, severity, and evidence into a 0-100 score, with bidirectional (A→B and B→A) analysis and management recommendations (alternatives, dose adjustments, monitoring).

Primary use cases: pre-prescription interaction screening, polypharmacy review, mechanistic interpretation of a flagged drug pair.

Notes

It is a reasoning layer over ToolUniverse; without the MCP server registered, the tool calls fail. The skill emphasizes Phase II UGT/glucuronidation interactions in addition to CYP, and explicitly documents null results in its report. Outputs are decision-support reasoning, not clinical advice. ToolUniverse ships ~68 such skills; the research, repurposing, target-validation, synergy, and precision-oncology workflows are catalogued separately.

Sources

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