HarvestAPI MCP | Oauth 2.0 HarvestAPI connector for AI agents

CALL ANY TOOL

List and create time entries, manage projects and tasks, and pull invoice and billing data.

harvest_time_entries_list

List time entries

List time entries with user, project, and date range filters.

Parameters

Name

Type

Required

Description

user_id

integer

Optional

Filter by user ID

project_id

integer

Optional

Filter by project ID

from

string

Optional

Start date YYYY-MM-DD

to

string

Optional

End date YYYY-MM-DD

page

integer

Optional

Pagination page

harvest_time_entry_create

Create time entry

harvest_projects_list

List projects

harvest_project_get

Get project

harvest_invoices_list

List invoices

Build your Agent

Drop the toolkit in, point it at the user, and your time tracking agent can use HarvestAPI from the first run.

Copied

import { ScalekitClient } from "@scalekit-sdk/node";
import { DynamicStructuredTool } from "@langchain/core/tools";
import { createReactAgent } from "@langchain/langgraph/prebuilt";
import { z } from "zod";

const sk = new ScalekitClient(envUrl, clientId, clientSecret);

const { tools } = await sk.tools.listScopedTools("user_123", {
  filter: { connectionNames: ["harvestapi"], toolNames: ["harvest_time_entries_list", "harvest_time_entry_create", "harvest_projects_list"] },
  pageSize: 100,
});

const lcTools = tools.map((t) => new DynamicStructuredTool({
  name: t.tool.definition.name,
  description: t.tool.definition.description,
  schema: z.object({}).passthrough(),
  func: async (args) => {
    const { data } = await sk.tools.executeTool({
      toolName: t.tool.definition.name,
      identifier: "user_123",
      params: args,
    });
    return JSON.stringify(data);
  },
}));

const agent = createReactAgent({ llm, tools: lcTools });

Copied

import { ScalekitClient } from "@scalekit-sdk/node";
import OpenAI from "openai";

const sk = new ScalekitClient(envUrl, clientId, clientSecret);
const openai = new OpenAI();

const { tools } = await sk.tools.listScopedTools("user_123", {
  filter: { connectionNames: ["harvestapi"], toolNames: ["harvest_time_entries_list", "harvest_time_entry_create", "harvest_projects_list"] },
  pageSize: 100,
});

const llmTools = tools.map((t) => ({
  type: "function",
  function: {
    name: t.tool.definition.name,
    description: t.tool.definition.description,
    parameters: t.tool.definition.input_schema,
  },
}));

const resp = await openai.responses.create({
  model: "gpt-4o", input: prompt, tools: llmTools,
});

import { ScalekitClient } from "@scalekit-sdk/node";
import Anthropic from "@anthropic-ai/sdk";

const sk = new ScalekitClient(envUrl, clientId, clientSecret);
const anthropic = new Anthropic();

const { tools } = await sk.tools.listScopedTools("user_123", {
  filter: { connectionNames: ["harvestapi"], toolNames: ["harvest_time_entries_list", "harvest_time_entry_create", "harvest_projects_list"] },
  pageSize: 100,
});

const llmTools = tools.map((t) => ({
  name: t.tool.definition.name,
  description: t.tool.definition.description,
  input_schema: t.tool.definition.input_schema,
}));

const msg = await anthropic.messages.create({
  model: "claude-sonnet-4-6", max_tokens: 1024,
  tools: llmTools,
  messages: [{ role: "user", content: prompt }],
});

Copied

import { Agent } from "@google/adk/agents";
import {
  MCPToolset, StreamableHTTPConnectionParams,
} from "@google/adk/tools/mcp";

const toolset = new MCPToolset({
  connectionParams: new StreamableHTTPConnectionParams({
    url: "https://mcp.scalekit.com/harvestapi",
    headers: { Authorization: `Bearer ${userScopedToken}` },
  }),
});

const agent = new Agent({
  name: "agent", model: "gemini-2.0-flash",
  tools: await toolset.getTools(),
});

Try these prompts

Paste any prompt into your agent to start using HarvestAPI.

Search & recall

Copy the prompt

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List my time entries for this week.

Copy the prompt

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How many hours did [person] log on [project] this month?

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Show all time entries for [project] today.

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Which projects have exceeded budget this quarter?

Action & logging

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Log 2 hours on [project] today: [notes].

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Create a time entry for [task] on [date].

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Update notes on time entry [id].

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Delete time entry [id].

Invoices & billing

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List all open invoices.

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Which invoices are overdue?

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Get billing summary for [client] this month.

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Total billable hours by client this quarter.

SEE HOW AUTH WORKS

Users authorize HarvestAPI once. Their credentials stay vaulted, every call is checked, and every action is logged.

1

Authorize

Your user connects

HarvestAPI

once. We tie it to their identity and the meetings they approved — no shared bot account, no org-wide access

Who:

user ‘A’

when:

Once per user

access:

Limited to user

2

Store

Their

HarvestAPI

token lives in a vault scoped to them. User A's meetings are never reachable by an agent acting for user B, even on the same connection

vault:

encrypted

scope:

per-user

tokens:

auto-refreshed

3

Resolve

When your agent calls a

HarvestAPI

tool, we fetch the right token server-side. It never touches your agent, never appears in the LLM context, never shows up in your logs

speed:

~40ms

check:

before every call

seen by:

nobody

4

Audit

Every

HarvestAPI

tool call is logged — who triggered it, which meeting was fetched, what came back. 90 days of history, tied to the user who authorized it

history:

90 days

export:

SIEM-ready

logged:

every call

Test other agents

Same per-user auth pattern across other time tracking agents and MCP connectors. Working code, live demos, fork what fits.

ENGINEERING

Engineering standup agent

Aggregate GitHub and GitLab activity, link to Jira, and post a daily standup digest to Slack. No async updates.

ENGINEERING

DevOps assistant agent

Triage GitHub incidents, open Linear tickets, and notify the on-call channel in Slack with context already attached.

Why Scalekit

Secure your agent's access. Connectors ship in minutes

Other connector libraries treat auth as a demo afterthought. Scalekit starts with user identity, scope enforcement, and audit.

01.

Shared tokens break per-user analytics

A shared token looks fine in a demo. In production every call looks like a service account. Scalekit resolves the real user credential so attribution, audit, and scope stay accurate.

// shared token
 audit → bot_service_account
 user_filter → broken

 // scalekit
 audit → user_abc
 scope → enforced ✓

02.

Authentication is not authorization

03.

Multi-tenancy is architectural

04.

HarvestAPI today. Others tomorrow.

“Our agents act across Salesforce, Gong, Google Drive, and more, on behalf of every customer. Scalekit behind the scenes meant we can keep adding tools without ever rebuilding how credentials or tool calling work.”

Venu Madhav Kattagoni

Head of Engineering / Von

FAQs

Frequently Asked Questions

Does the agent access HarvestAPI as the user or as a shared key?
As the user. Each workspace member authorizes once and Scalekit resolves their credential at request time. Audit logs attribute every action to that user, not a shared service account.

Where is the HarvestAPI oauth 2.0 stored?
In Scalekit's managed AES-256 token vault, namespaced per tenant. Refresh is automatic. Revocation is a single dashboard action. Tokens never appear in prompts, logs, or LLM context.

Can I limit what the agent is allowed to do in HarvestAPI?
Yes. Pass a tool name filter to listScopedTools so the time tracking agent only sees the subset you authorize. Pre-API-call scope checks block out-of-policy actions before the request reaches HarvestAPI.

What happens when a user revokes HarvestAPI access?
The connection is invalidated on the next tool call. Subsequent requests for that user fail closed with a clear error. Other users in the tenant remain unaffected. The event is logged for audit.

Can the agent log time on behalf of other team members?
Only if the authorizing user has admin rights in Harvest. Regular user tokens log time for that user only. Admin tokens can log for others if account-level settings permit cross-user time entry.

HarvestAPI

Tools your time tracking agent reaches for on HarvestAPI, scoped per user.