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feat: flag unportable tool schemas in all three clients

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Closes #1005

A tool schema can be perfectly legal JSON Schema and still be rejected by
the client the server is meant to run against — Go's `jsonschema` emits a
bare `true` for `interface{}`, which the SDK accepts and Claude Code
refuses with an opaque "Invalid input". The Inspector passed it through
silently.

Adds `core/json/schemaLint.ts`, a portability lint over a tool's
inputSchema/outputSchema, and surfaces one shared verdict everywhere:
the CLI's `--strict` report (exit 6 on an error-severity finding), the
TUI's tool list marker + detail pane, and the web Tools sidebar flag +
detail section.

Deliberately not a JSON Schema validator: a census of 617 public servers
found zero that fail the SDK's own parse, so a conformance check would
report nothing on real servers. Each rule is instead a construct that is
legal JSON Schema and known to be refused or mishandled by a shipping
client — a bare boolean in a schema position, an array-form `type`, a
remote `$ref`, a schema with no validation keyword, a non-object root.

`test-servers/configs/unportable-schemas-http.json` exercises every rule,
via a new `rawToolSchemas` override — the Zod-built presets cannot emit
any of these shapes, which is the same reason a real server only hits
this when its schemas come from another generator.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UL9retfvAXRgvi6EWk4SY4
Signed-off-by: cliffhall <cliff@futurescale.com>
This commit is contained in:
cliffhall 2026-08-25 01:18:53 -04:00
commit 2f9e0901c1
1 changed files with 1979 additions and 13 deletions
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15
AGENTS.md
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@ -157,7 +157,20 @@ v2/main/
│ │ # Shared by BOTH form builders — web SchemaForm
│ │ # and TUI schemaToForm — since each dispatches on
│ │ # a single `type` string and would otherwise miss
│ │ # a nullable field entirely — #1928/#2015)
│ │ # a nullable field entirely — #1928/#2015;
│ │ # schemaLint.ts: tool-schema PORTABILITY lint —
│ │ # constructs that are legal JSON Schema and are
│ │ # refused or mishandled by real MCP clients (a bare
│ │ # `true` in `properties`, an array-form `type`, a
│ │ # remote `$ref`, a schema carrying no validation
│ │ # keyword, a non-object root). Deliberately NOT a
│ │ # validator: a census of 617 public servers found 0
│ │ # that fail the SDK's own parse, so a conformance
│ │ # check reports nothing on real servers. ONE verdict
│ │ # for all three clients — the CLI's `--strict` report
│ │ # (exit 6), the TUI's tool detail pane, the web Tools
│ │ # tab — so they cannot disagree about what is
│ │ # portable; the report TEXT is shared too — #1005)
│ ├── logging/ # Silent pino logger singleton
│ ├── mcp/ # InspectorClient runtime + state stores
│ │ # (uriTemplate.ts: RFC 6570 parse/classify/expand.