plaid-devx-mcp

Fire a test webhook (sandbox only)

plaid_sandbox_fire_webhook

Fire a sandbox webhook on an Item to test your webhook handler. Pick a webhook code to simulate Plaid events like SYNC_UPDATES_AVAILABLE.

Instructions

Calls /sandbox/item/fire_webhook so you can exercise your webhook handler. The Item must have been created with a webhook URL.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "item_id": "<item_id>"
    },
    "name": "plaid_sandbox_fire_webhook"
  }
}

Input Schema

Name	Required	Description	Default
`item_id`	Yes	item_id from plaid_sandbox_item_create (or a raw access_token you already hold)
`webhook_code`	No		SYNC_UPDATES_AVAILABLE

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Sep 15, 2026

TDQS

A4.4/5.0

Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the behavioral disclosure burden, and it does so well: it states the REST call, the prerequisite webhook URL, and the intended side effect of driving the user's handler. It does not go into response or error behavior, but for a sandbox webhook trigger these are minor omissions.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two short sentences: one front-loads the endpoint and purpose, the other gives the key prerequisite. There is no filler and every sentence earns its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a 2-parameter, no-output-schema sandbox test action, the description gives the endpoint, reason to call it, and the item validity condition. It could note that a webhook callback will actually be delivered and maybe mention the default event, but those are inferable from the name and schema defaults.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The schema already documents item_id's allowed source (item_create or raw access_token) and webhook_code's enum/default. The description adds a useful validity constraint on item_id: it must belong to an Item created with a webhook URL, which is not present in the schema and materially affects whether the call succeeds.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description names the exact endpoint (/sandbox/item/fire_webhook) and the real purpose ('exercise your webhook handler'), so an agent immediately knows what operation this performs. The title's 'sandbox only' also separates it from production Plaid tools, and no sibling tool overlaps with webhook-trigger testing.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

It explicitly says when to use the tool (to exercise a webhook handler) and gives a necessary precondition (the Item must have been created with a webhook URL). It does not name specific alternatives or say 'do not use in production,' but the sandbox-only title and the unique webhook-testing purpose provide enough situational guidance.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.