io.github.cyanheads/pubchem-mcp-server
pubchem-mcp-server
io.github.cyanheads/pubchem-mcp-server costs 4 599 tokens of context per session. It has 10 tool definitions. That is 2.3 % of a 200k window. Measured 2026-10-03.
Search PubChem compounds, properties, safety data, bioactivity, and cross-references.
alive probed 2026-10-03 · HTTP 200
10tools
4.6ktokens for the tool definitions
2.3 %of a 200k context window
879 msto initialize
152 msto list tools
- Endpoint
- https://pubchem.caseyjhand.com/mcp (streamable-http)
- Host
- pubchem.caseyjhand.com
- Protocol
- 2025-11-25
- Reports itself as
- pubchem-mcp-server 0.6.5
- Capabilities
- logging, prompts, resources, tools
- Instructions
- 883 characters
- Repository
- https://github.com/cyanheads/pubchem-mcp-server
- Registry
- active, updated 2026-09-25 · registry entry
- Reachable
- 2 of the last 2 probes
Most expensive tools
| Tool | Tokens | Share of this server |
|---|---|---|
| pubchem_search_compounds | 951 | 21 % |
| pubchem_get_compound_details | 950 | 21 % |
| pubchem_get_bioactivity | 483 | 11 % |
| pubchem_get_compound_3d_structure | 472 | 10 % |
| pubchem_get_compound_interactions | 397 | 9 % |
History
We add a row when the result changes. A server with no change keeps its last row.
| Probed | Result | Init | Tools | Tokens |
|---|---|---|---|---|
| 2026-10-03 20:37 | alive | 879 ms | 10 | 4.6k |
| 2026-10-03 17:53 | alive | 409 ms | 10 | 4.6k |
Badge
[](https://mcp-pulse.ulehla.dev/s/io.github.cyanheads/pubchem-mcp-server)