Add URL Elicitation cases

[evalstate]

Add URL Elicitation cases (normal ElicitationRequest + -32042 error style).

Description

Opening for discussion -- this covers the basic case; I wonder do we want the ElicitationRequest to block and send a callback URL? Happy to add this, but wanted to discuss with @olahungerford @cliffhall before going that far.

Motivation and Context

How Has This Been Tested?

Breaking Changes

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update

Checklist

• I have read the MCP Protocol Documentation
• My changes follows MCP security best practices
• I have updated the server's README accordingly
• I have tested this with an LLM client
• My code follows the repository's style guidelines
• New and existing tests pass locally
• I have added appropriate error handling
• I have documented all environment variables and configuration options

Additional context

[cliffhall]

Can we have just one trigger-url-elicitation-request tool with a checkbox that says whether to execute it via the error path? Similar to how simulate-research-query has a checkbox for 'ambiguous query' that causes it to send an elicitation request for clarification.

[evalstate]

Can we have just one trigger-url-elicitation-request tool with a checkbox that says whether to execute it via the error path? Similar to how simulate-research-query has a checkbox for 'ambiguous query' that causes it to send an elicitation request for clarification.

I've made that update and kept this bare bones for the moment.

[cliffhall]

@evalstate I'm adding URL Elicitation support to the Inspector (PR#1108) for testing this.

Meanwhile, would you mind making a tiny driveby change while you're at it, and reorder the Get Roots List Tool up the list with the other Get tools?

From

To

[cliffhall]

@evalstate If I choose the error path checkbox, I just get an error response:

But it looks like I should also get a list of elicitiations:

[evalstate]

Hi Cliff, that tool is grouped there because the order is set by whether or not it's conditional (e.g. client capability).

I've taken a look at this (I have been testing from a Python client) and seems we need this fix in the TypeScript Client SDK: modelcontextprotocol/typescript-sdk#1578

I've also made a small push to this branch to unpack the message:

Don't think there's a good alternative than an SDK change unfortunately....