Environment variable warnings shown for all servers, not just the one being queried

[filipeestacio]

Issue: Environment variable warnings shown for all servers, not just the one being queried

Description

When running mcp-cli info <server>, warnings about missing environment variables are displayed for ALL servers in the config, not just the server being queried. This creates unnecessary noise, especially when using mcp-cli with AI agents.

Steps to Reproduce

1. Create config with multiple servers, some using ${VAR} placeholders
2. Run mcp-cli info chrome-devtools (a server without env vars)
3. See warnings for all OTHER servers' missing env vars

Expected Behavior

Warnings should only appear for environment variables referenced by the server being queried (or all servers when running mcp-cli info without arguments).

Actual Behavior

[mcp-cli] Warning: Missing environment variable: ${MCP_EMAIL_SERVER_ACCOUNT_NAME}
[mcp-cli] Warning: Missing environment variable: ${CONTEXT7_API_KEY}
...
# Even though I'm only querying chrome-devtools which doesn't use these

Related

• Issue only show STDERR with -v or -debug #17 discusses showing STDERR only with -v/--debug
• This issue is more specific: warnings should be scoped to the queried server

Proposed Solution

1. Lazy evaluation: Only substitute env vars for the server(s) being accessed
2. OR: Filter warnings to only show for relevant servers
3. Combine with only show STDERR with -v or -debug #17: Only show warnings in debug mode

Workaround

MCP_STRICT_ENV=false mcp-cli info chrome-devtools 2>/dev/null

[filipeestacio]

I'm happy to work on this if you'd like? Just wondering if you have any insights or if this is by design.