Add tool annotations and server instructions - #31
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Tools can now call MarkReadOnly to expose readOnlyHint/openWorldHint in tools/list, via a new IMCPToolAnnotations interface that TMCPToolBase and its two generic variants implement; tools/list adds the hints only when a tool supports the interface, so an IMCPTool built without the base classes is unaffected. TMCPSettings gains an Instructions property (settings.ini Server.Instructions, or set in code), surfaced as the optional "instructions" field of the initialize response per the MCP spec.
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Summary
IMCPToolAnnotationsinterface (implemented byTMCPToolBaseand its two generic variants) with aMarkReadOnly(OpenWorld: Boolean = False)helper;tools/listincludesreadOnlyHint/openWorldHintfor any tool that supports it, and leaves outannotationsentirely for tools that don't, so this is backward compatible with any existingIMCPToolimplementation.TMCPSettings.Instructions(settings.ini:Server.Instructions), surfaced as the optional top-levelinstructionsfield of theinitializeresponse per the MCP spec, omitted when empty.settings.ini.example.Why
Per the spec, clients MAY add
instructionsto their system prompt and MAY use tool annotations to decide things like parallel execution or auto-approval of read-only calls. Several consuming projects (Context4D among them) expose only read-only, local lookups and want to say so explicitly instead of clients assuming the worst-case defaults.Test plan
dcc32/dcc64build of a consumer project (Context4D) against this branch, Debug and Release, Win32 and Win64instructionsininitializeandreadOnlyHint:trueon every tool intools/list