Remove non-spec progress/update method from MCP parser

[jhrozek]

Summary

The MCP parser's methodHandlers map in pkg/mcp/parser.go contains an entry for "progress/update" which is not a valid method in any MCP specification version (2024-11-05, 2025-03-26, 2025-06-18, or 2025-11-25).

The actual spec-defined method for progress notifications is notifications/progress, which is also correctly handled in the map.

Details

File: pkg/mcp/parser.go, line 194

"progress/update":            handleProgressMethod,

• progress/update maps to handleProgressMethod (extracts progressToken as string only)
• notifications/progress maps to handleProgressNotificationMethod (extracts progressToken as both string and numeric)

The extra entry is functionally harmless since no real MCP client/server would send this method name, but it could confuse maintainers into thinking it's a real spec method.

Suggested Fix

Remove the "progress/update" entry from the methodHandlers map. If it was intentionally kept for backwards compatibility with a non-standard implementation, add a comment explaining why.

Found During

Code review of #4157 (PR adding notifications/elicitation/complete to parser).

🤖 Generated with Claude Code

[majiayu000]

Hi, I've been looking into this and traced the root cause.

Proposed approach: Delete the single line '"progress/update": handleProgressMethod,' from the methodHandlers map in pkg/mcp/parser.go:194. Verify that handleProgressMethod is not referenced elsewhere (if only used by this deleted entry, consider removing the function too). Run go build and go test to validate.

I'll open a draft PR shortly. Happy to adjust based on your preference.