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Hamza
b1f0eafbf7
MCP stdio is newline-delimited JSON, so one tool result is one message and has to fit the client's read buffer whole; there is no streaming of part of one. The TypeScript SDK's stdio transport defaults to 10 MiB and hosts rarely raise it, so a document whose tree went past that killed the server: the client stopped reading, the pipe broke, and every later call in the session failed. The tree is now reported at the deepest depth that fits, found by bisection, with a `truncated` object giving the depth asked for, the depth used, both sizes, the limit and a pointer to get_node for reading one subtree deeply. `maxBytes` lets a caller that knows its own buffer say so; the default is 8 MiB, leaving the envelope 2 MiB of the usual 10. The size is measured as the transport sends it -- pretty-printed and then escaped inside the text block, which adds about a tenth (342,136 bytes of tree became 379,954 on the wire in the fixture). A kilobyte is reserved for the marker itself, which is added after the measurement. A limit below even the shallowest tree still answers, at depth 0, with the marker saying so: there is nothing smaller to send, and an error would leave the caller with nothing at all. The tool description now says that each level of depth multiplies the response and points at get_node, which the report notes would have been enough on its own to avoid the crash. Fixes #912.