Source Intelligence

DisclaimerUnofficial, and not affiliated with Anthropic. Nearly all of this is read straight out of what ships: npm bundles, captured prompts, published docs. Anthropic's own notes go in verbatim, marked as theirs. The rest is my reading, and every entry carries the strings behind it. If one looks wrong, vote it down and say why.

All of v2.1.248 Home All releases olderv2.1.247 v2.1.250newer
Claude Code v2.1.248

Missing MCP capabilities return empty instead of erroring

You'll notice
Useful3 Signal1
MCP

MCP servers that advertise no tools or prompts return empty instead of erroring.

What

A server that does not advertise tools, resources, resource templates or prompts now short-circuits to an empty list rather than making the call.

Details
  • All four listings go through one memoizing wrapper keyed on server name plus config, with failures clearing the cache entry and the error recorded on the returned list.
  • tools/list takes an extra branch for newer protocol versions.
Evidence

resources/templates/list

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

See this entry in the whole of v2.1.248 →