opa-mcp-server

Tool annotations match behaviour

5 read-only tools perform write/delete/exec — rego_check_schema (line 151: writeFile(schemaFile, JSON.stringify(inlineSchema), 'utf8')); rego_format (line 44: /^(\d+)\.(\d+)\.(\d+)/.exec(v)); opa_exec (line 172: opa.exec()

Either remove the readOnlyHint:true annotation, or remove the write/delete call from the tool handler.

Destructive tools are labelled

1 tool perform destructive updates without destructiveHint — rego_check_schema deletes at line 202 (rm(tempDir, { recursive: true, force: true }))

Add destructiveHint:true to any tool whose handler calls .delete(), .upsert(), .update(), unlink, rm, DELETE, DROP, REPLACE INTO, or any operation that overwrites existing data.

Descriptions match behaviour

1 tool describes read intent but its handler mutates — rego_check_schema (line 151: writeFile(schemaFile, JSON.stringify(inlineSchema), 'utf8'))

Rename the tool, rewrite the description, or move the side-effect into a separate clearly-named tool.

Tool inputs are validated

Only 10/52 tool handlers declare input schemas (19%)

Declare an inputSchema with zod/joi/yup on every tool definition.

Tool handlers catch errors

Only 18/52 tool handlers wrap calls in try/catch (35%)

Wrap each tool handler body in try/catch and return a structured error response.

Shell command execution

14 child_process calls — runs shell commands

Prefer library functions over shell-outs. If you must shell out, ensure all inputs are properly escaped.

Tool description accuracy

rego_check_schema: description implies read-only but handler writes/deletes/executes

Update tool descriptions to accurately reflect all capabilities — especially write, delete, or execute operations.