Candor vs Opentargets

A side-by-side look at the Candor and Opentargets MCP servers: transport, auth, tools, quality signals, and the config to install either one in Claude, Cursor, Windsurf or VS Code.

Candor logoCandorBiology & Bioinformatics · Local subprocess (stdio)Per-function effect analysis for agents: blast radius, what reaches the network, gate verdicts.45FairAuth: not declaredOpentargets logoOpentargetsBiology & Bioinformatics · Local subprocess (stdio)Open Targets MCP server for targets, diseases, drugs, variants, and evidence63GoodAuth: no auth required

Verdict: choose Candor for biology & bioinformatics work as a local process; choose Opentargets for biology & bioinformatics as a local process. You can also run both side by side in one mcpServers block.

Which MCP server should you choose?

Candor logoChoose Candor when

  • You need dedicated capabilities in the Biology & Bioinformatics domain.
  • You prefer a local stdio subprocess transport.
Explore Candor

Opentargets logoChoose Opentargets when

  • You need dedicated capabilities in the Biology & Bioinformatics domain.
  • You prefer a local stdio subprocess transport.
  • Its auth model fits you: No auth required.
  • You have the keys it needs: MCP_TRANSPORT, FASTMCP_SERVER_HOST, FASTMCP_SERVER_PORT, OPEN_TARGETS_API_URL, OPEN_TARGETS_RATE_LIMIT_RPS, OPEN_TARGETS_RATE_LIMIT_BURST, OPEN_TARGETS_RATE_LIMIT_ENABLED.
  • You want tools like get_target_alternative_genes, get_target_associated_diseases, get_target_chemical_probes.
Explore Opentargets

Feature & specification comparison

Rows where the two servers differ are marked.

SpecCandor logoCandorOpentargets logoOpentargets
CategoryBiology & BioinformaticsBiology & Bioinformatics
Quality signal45/100 · Fair63/100 · Good
Install commandConfirmedConfirmed
TransportLocal subprocess (stdio)Local subprocess (stdio)
AuthNot declaredNo auth required
PricingNot declaredFree
Required env varsNone listedMCP_TRANSPORTFASTMCP_SERVER_HOSTFASTMCP_SERVER_PORTOPEN_TARGETS_API_URLOPEN_TARGETS_RATE_LIMIT_RPSOPEN_TARGETS_RATE_LIMIT_BURSTOPEN_TARGETS_RATE_LIMIT_ENABLED
Verified ownerCommunity listingCommunity listing
GitHub stars119
Directory activity 2 views 0 installs 0 upvotes 4 views 0 installs 0 upvotes
ToolsNot listed68

Tools & capabilities

Candor tools

No tool names declared yet. Check the project README from the listing page.

Opentargets tools 68

  • get_target_alternative_genesList alternate gene symbols and database cross-references for a target.
  • get_target_associated_diseasesList diseases linked to a target with association scores.
  • get_target_chemical_probesList available chemical probes and their quality metrics.
  • get_target_classReturn ChEMBL target class annotations for a gene.
  • get_target_depmap_essentialityFetch DepMap CRISPR essentiality scores across cell lines.
  • get_target_expressionReturn baseline expression measurements for a target across biosamples.
  • get_target_genetic_constraintFetch genetic constraint metrics (gnomAD) for a target.
  • get_target_hallmarksReturn cancer hallmark annotations associated with a target.
  • get_target_homologuesRetrieve cross-species homologues for a target gene.
  • get_target_infoRetrieve core identity details for a target gene.
  • get_target_interactionsRetrieve protein interaction partners for a target from curated databases.
  • get_target_known_drugsReturn compounds with known activity on the target.
  • +56 more on the listing page

Ready-to-paste client configs

Paste either block (or both) into your client config, e.g. claude_desktop_config.json or ~/.cursor/mcp.json. We only show a config when the install command is confirmed.

Candor

mcpServers (Claude Desktop / Cursor)
{
  "mcpServers": {
    "candor": {
      "command": "npx",
      "args": [
        "-y",
        "candor-ts"
      ]
    }
  }
}

Opentargets

mcpServers (Claude Desktop / Cursor)
{
  "mcpServers": {
    "opentargets": {
      "command": "uvx",
      "args": [
        "--from",
        "git+https://github.com/nickzren/opentargets-mcp",
        "opentargets-mcp"
      ],
      "env": {
        "MCP_TRANSPORT": "YOUR_MCP_TRANSPORT_HERE",
        "FASTMCP_SERVER_HOST": "YOUR_FASTMCP_SERVER_HOST_HERE",
        "FASTMCP_SERVER_PORT": "YOUR_FASTMCP_SERVER_PORT_HERE",
        "OPEN_TARGETS_API_URL": "YOUR_OPEN_TARGETS_API_URL_HERE",
        "OPEN_TARGETS_RATE_LIMIT_RPS": "YOUR_OPEN_TARGETS_RATE_LIMIT_RPS_HERE",
        "OPEN_TARGETS_RATE_LIMIT_BURST": "YOUR_OPEN_TARGETS_RATE_LIMIT_BURST_HERE",
        "OPEN_TARGETS_RATE_LIMIT_ENABLED": "YOUR_OPEN_TARGETS_RATE_LIMIT_ENABLED_HERE"
      }
    }
  }
}

Frequently asked questions

Candor is categorized under Biology & Bioinformatics and uses a local stdio subprocess. Opentargets belongs to Biology & Bioinformatics and uses a local stdio subprocess. Pick Candor for biology & bioinformatics work and Opentargets for biology & bioinformatics.

Copy the mcpServers block from the config section on this page into your client's config (for example claude_desktop_config.json or ~/.cursor/mcp.json), then fully restart the client.

Candor has no declared pricing — check the project's own site. Opentargets is listed as free. Auth: no auth required. If a server needs environment variables such as API keys, define them under the env key in your client's MCP config.

Yes. MCP clients support multiple servers: add candor and opentargets as separate keys in the same mcpServers object, and your assistant will call tools from either one.

On AllMCPs, Candor has a quality signal of 45/100 (Fair) with 2 views, 0 installs and 1 GitHub stars. Opentargets has 63/100 (Good) with 4 views, 0 installs and 19 GitHub stars.