# Cyanheads Chembl MCP server

Source: https://glimind.com/server/mcp-registry%2Fio.github.cyanheads%2Fchembl-mcp-server
Registry id: `mcp-registry/io.github.cyanheads/chembl-mcp-server`
Status: live (checked 2026-10-26T19:52:43.000Z)

## Verdict

Cyanheads Chembl MCP server answered 99.81% of Glimind's liveness checks over 30 days, better than 24% of MCP servers, with 646 ms median handshake and 14 outages in 90 days. Its agent-readiness grade is A (96/100) across 7 tools, costing an agent about 3,672 tokens to load. Checked every few minutes; no tool is ever called.

## Measurements (30 days)

| Metric | Value | Better than |
|---|---|---|
| Uptime, 30 days | 99.81% | 24% of MCP servers |
| Median handshake latency | 646 ms | 40% of MCP servers |
| p95 handshake latency | 2915 ms | — |
| Checks in 30 days | 4,876 | — |
| Outages, 90 days | 14 | — |
| Median recovery | 5 min | — |
| Agent-readiness score | 96/100 (A) | 82% of MCP servers |
| Tools | 7 | — |
| Tool-list size for an agent | ~3,672 tokens | 42% of MCP servers |
| Days observed | 29 | — |

## Install

```json
{
  "mcpServers": {
    "cyanheads-chembl-mcp-server": {
      "type": "http",
      "url": "https://chembl.caseyjhand.com/mcp"
    }
  }
}
```

Claude Code:

```sh
claude mcp add --transport http cyanheads-chembl-mcp-server https://chembl.caseyjhand.com/mcp
```

## Tools (8)

- `chembl_dataframe_describe`: List the tables and columns staged on a canvas by chembl_get_bioactivities — inspect before calling chembl_dataframe_query to write correct SQL. Returns each ta
- `chembl_dataframe_drop`: Drop a named staged table from a canvas. Opt-in.
- `chembl_dataframe_query`: Run a read-only SQL SELECT over the bioactivity rows chembl_get_bioactivities staged on a canvas — rank, group, dedupe, and aggregate across the FULL set, not t
- `chembl_get_assay`: Assay provenance behind a bioactivity row: description, type (binding / functional / ADMET / toxicity), the target it measures, organism, and ChEMBL's 1–9 confi
- `chembl_get_bioactivities`: The flagship compound↔target bioactivity bridge: measurements for a molecule (target deconvolution / selectivity), a target (lead finding), or both together (ho
- `chembl_get_drug_info`: Pharmacology for a drug (molecule): mechanism(s) of action, the molecular target(s) it acts on, action type (inhibitor / agonist / …), first-approval year, and 
- `chembl_search_molecules`: Discovery entry point for compounds. Find by name / ChEMBL ID / InChIKey with the default search_type=name (supply query), or run a structure search with search
- `chembl_search_targets`: Resolve a protein/gene/UniProt accession to the ChEMBL target ID that chembl_get_bioactivities needs for the target→leads workflow. Supply at least one of acces

Measured by Glimind (https://glimind.com): MCP handshake + tool list only, no tool is ever called. CC BY 4.0.