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[Client] Expose the capabilities the server declared - #542
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The client parsed the server's capabilities during the handshake but kept none of them. Keep them in the client state and expose them through Client::getServerCapabilities(), read from server/discover on 2026-07-28.
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The SDK's client now keeps what the server declared — from `initialize`, or from `server/discover` on 2026-07-28 (modelcontextprotocol/php-sdk#542) — and the bundle's connection forwards it once chr-hertel/ai's "Expose the server capabilities on ServerConnectionInterface" lands. Until then the check skips itself rather than failing against the bundle's `main`.
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…face` mcp/sdk 0.9 adds `Client::getServerCapabilities()`, returning what the server declared in `initialize` or, on 2026-07-28, in `server/discover` (modelcontextprotocol/php-sdk#542). The connection already forwards the other three things the server declares about itself - info, protocol version and instructions - so this completes the set.
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…face` mcp/sdk 0.9 adds `Client::getServerCapabilities()`, returning what the server declared in `initialize` or, on 2026-07-28, in `server/discover` (modelcontextprotocol/php-sdk#542). The connection already forwards the other three things the server declares about itself - info, protocol version and instructions - so this completes the set.
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…face` mcp/sdk 0.9 adds `Client::getServerCapabilities()`, returning what the server declared in `initialize` or, on 2026-07-28, in `server/discover` (modelcontextprotocol/php-sdk#542). The connection already forwards the other three things the server declares about itself - info, protocol version and instructions - so this completes the set.
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The client parses the server's capabilities in
initializebut keeps onlyserverInfoandinstructions, so a caller can't check forcompletions,loggingorresources.subscribebefore relying on them. Found while building the interop suite in #540.Changes
Client::getServerCapabilities(): ?ServerCapabilities, taken frominitialize, or fromserver/discoveron 2026-07-28.nulluntil a server declared them.ClientStateInterface/ClientStategainsetServerCapabilities()/getServerCapabilities().BC
Adding methods to
ClientStateInterfacebreaks custom implementations, hence[BC Break]in the CHANGELOG.Protocolalways creates its ownClientStateand there's no way to inject another, so I don't expect any exist.