fix: wrap top-level array params in anyOf to also accept JSON-encoded strings#261
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cheafon wants to merge 1 commit into
Open
fix: wrap top-level array params in anyOf to also accept JSON-encoded strings#261cheafon wants to merge 1 commit into
cheafon wants to merge 1 commit into
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… strings
Some MCP clients (e.g. Claude Code, Cursor) double-serialize top-level
array parameters, sending them as a JSON string (e.g. "[{...}]") instead
of an actual array. This caused `notion-create-pages` to fail with:
Invalid input: expected array, received string
The existing `withStringFallback` already handles this for object-typed
params by wrapping them in `anyOf: [schema, { type: 'string' }]`.
This commit applies the same treatment to array-typed params.
At runtime, `deserializeParams()` in proxy.ts already correctly converts
the JSON-encoded string back to an array, so no runtime changes are needed.
Fixes: makenotion#176
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Problem
When calling
notion-create-pagesfrom Claude Code (or Cursor), thepagesarray parameter arrives as a JSON-encoded string instead of an actual array,
causing validation to fail:
This is a known MCP client behavior where top-level array parameters get
double-serialized (
JSON.stringify'd) before being sent.Root Cause
withStringFallback()inparser.tsalready handles this for objectparameters by wrapping them in
anyOf: [schema, { type: 'string' }]—allowing both the native type and a JSON-encoded string. However, this
treatment was missing for array parameters.
The runtime fix (
deserializeParams()inproxy.ts) already correctlyconverts
"[...]"strings back to arrays — so only the schema validationneeded to be updated.
Fix
Apply the same
anyOf: [array, string]wrapping to array-typed parametersin
withStringFallback(). This is consistent with the existing objecthandling and resolves the schema validation error.
Testing
parser.test.tscovering an array request bodyparameter (mirrors the
notion-create-pages/pagesscenario)parser-multipart.test.tsexpectations to reflect thenew
anyOfstructure for array propertiesFixes #176