can1357/oh-my-pi · warning

yield parameters schema is invalid

Error message

yield parameters schema is invalid

What it means

After wrapping the (possibly sanitized) data schema, YieldTool validates the final `parameters` schema and stringifies it. If isValidJsonSchema fails — or any prior step in the try block throws — this Error is caught by the surrounding handler, which then falls back to a loose record schema embedding the error message, so structured output degrades gracefully rather than crashing.

Source

Thrown at packages/coding-agent/src/tools/yield.ts:340

			let dataSchema: Record<string, unknown>;
			if (sanitizedSchema !== undefined) {
				const resolved = dereferenceJsonSchema({
					...sanitizedSchema,
					description: schemaDescription,
				}) as Record<string, unknown>;
				if (hasUnresolvedRefs(resolved)) {
					throw new Error("schema contains unresolved $ref after dereferencing");
				}
				dataSchema = withSectionVariants(resolved);
			} else {
				this.strict = false;
				dataSchema = looseRecordSchema(
					schemaError ? schemaDescription : "Structured JSON output (no schema specified)",
				);
			}
			parameters = wrapYieldParameters(dataSchema);
			JSON.stringify(parameters);
			if (!isValidJsonSchema(parameters)) throw new Error("yield parameters schema is invalid");
		} catch (err) {
			const errorMsg = err instanceof Error ? err.message : String(err);
			parameters = wrapYieldParameters(
				looseRecordSchema(`Structured JSON output (schema processing failed: ${errorMsg})`),
			);
			validate = undefined;
			this.strict = false;
		}

		this.#validate = validate;
		this.#validateSection = validateSection;
		this.#rejectUnknownSections = rejectUnknownSections;
		this.#knownSectionLabels = knownSectionLabels;
		this.#isKnownSection = isKnownSection;
		this.description = prompt.render(yieldDescription, { hasOutputSchema: validate !== undefined });
		this.parameters = parameters;
	}

View on GitHub (pinned to 9690622007)

Solutions

1. Fix the supplied schema to be a valid JSON Schema (correct types, required keys referencing existing properties).
2. Inspect the fallback message in the tool parameters — it embeds the original error text (`schema processing failed: ...`).
3. Simplify the schema (fewer exotic keywords) and retry.
4. Omit the schema to use the default loose record schema.
5. null

Example fix

// before
yield({ schema: { type: "object", properties: { x: { type: "integer" } }, required: ["x","y"] } })
// after
yield({ schema: { type: "object", properties: { x: { type: "integer" } }, required: ["x"] } })

// pre-validate with the same validator family before constructing
if (!isValidJsonSchema(candidateSchema)) console.error("invalid schema", JSON.stringify(candidateSchema));

function isValidJsonSchema(s: unknown): boolean { /* validate against JSON Schema meta-schema */ return validateMetaSchema(s); }

try { const t = new YieldTool({ schema }); } catch (err) { console.warn("falling back to loose schema:", err.message); const t = new YieldTool({}); // loose record schema }

When it happens

Trigger: A wrapped yield parameters schema that violates JSON Schema constraints (e.g. invalid `type` values, conflicting keywords like `required` referencing nonexistent properties, unsupported combinations introduced by withSectionVariants/wrapYieldParameters).

Common situations: Schemas with provider-unsupported keywords or malformed constraints; deeply nested schemas that sanitization mutates into invalid form; custom validators flagging fields the provider would reject.

Understand the failure class

Background: Schema validation failed / invalid input schema: payload rejected because its shape doesn't match the expected schema — this error's family across 28 libraries.

Related errors

• Schema contains a circular object graph — cannot enforce str
• Schema node has no type, combinator, or $ref — cannot enforc
• Host tool "${name}" must provide a JSON Schema object
• Invalid ${scope} output schema: ${error}
• type must be a string or non-empty array of strings

AI-assisted analysis of can1357/oh-my-pi@9690622007 (2026-08-31). Data as JSON: /api/errors/3ad71169dcb065e7. Report an issue: GitHub.