upload_invoice_attachment
Upload an invoice attachment to Sanka from an already available base64 payload. Prefer this direct upload when the client can pass content_base64 reliably. For client-local PDFs or payloads that are too large or unreliable to pass as one content_base64 string, use start_invoice_attachment_upload,...
This record as markdown: /tools/sankahq-sanka-mcp/upload-invoice-attachment.md
What upload_invoice_attachment does on Sanka MCP Server
AI agents use upload_invoice_attachment to create or update resources in Sanka MCP Server, usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Sanka MCP Server environment.
Why upload_invoice_attachment is rated Medium
This tool creates new invoice attachments or associates them with invoice records, which is a reversible data modification operation. While it deals with financial documents (invoices), it does not itself move money or commit financial obligations—it only attaches supporting documentation.
From the tool's definition Tool description states 'Upload an invoice attachment' and 'Use the returned file_id in create_invoice or update_invoice', indicating it creates or modifies invoice-related data. The attachment is incorporated into invoice records through the returned file_id.
Attacks that exploit this kind of access
The rule that runs upload_invoice_attachment safely
PolicyLayer is an MCP gateway: it sits between your AI agents and Sanka MCP Server, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For upload_invoice_attachment, this is the rule to start with:
upload_invoice_attachment stays usable, but capped: an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.
The button opens the PolicyLayer dashboard: create your workspace, connect Sanka MCP Server, apply this rule, and every upload_invoice_attachment call is checked against it from then on.
Questions about upload_invoice_attachment
Upload an invoice attachment to Sanka from an already available base64 payload. Prefer this direct upload when the client can pass content_base64 reliably. For client-local PDFs or payloads that are too large or unreliable to pass as one content_base64 string, use start_invoice_attachment_upload, append_invoice_attachment_upload_chunk until done, then finish_invoice_attachment_upload. Use the returned file_id in create_invoice or update_invoice. It is categorised as a Write tool in the Sanka MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Sanka MCP Server MCP server in PolicyLayer and add a rule for upload_invoice_attachment: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Sanka MCP Server. Nothing to install.
upload_invoice_attachment is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the upload_invoice_attachment rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.
Set action: deny in the PolicyLayer policy for upload_invoice_attachment. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.
upload_invoice_attachment is provided by the Sanka MCP Server MCP server (sankahq/sanka-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
More on Sanka MCP Server, and thousands of servers like it.
This server
Across the catalogue