Hunter

Use this when the user wants to delete a company list by ID. Empty lists and dynamic lists are deleted immediately (status 204). A static list that still contains companies is deleted asynchronously: a background job removes its companies and the call returns status 202 (accepted) right away. Deleting a list cannot be undone from the API. Returns a not-found error if the list does not exist or belongs to another team. Free to call.

Use this when the user wants to delete a company-list folder by ID. Deleting a folder does not delete the company lists filed in it — each affected list keeps existing and simply becomes unfiled (its folder is cleared). Deleting a folder cannot be undone from the API. Only the folder's owner, a team admin, or the team owner may delete it. Succeeds with no content on success. Returns a not-found error if the folder does not exist, or a forbidden error if the user is not allowed to delete it. Free to call.

Use this when the user wants to permanently delete a custom-attribute definition, identified by ID. Per-lead values stored for the attribute are dropped and cannot be recovered. Free to call.

Use this when the user wants to remove a lead from their Hunter account, identified by ID. Free to call. Deleting a lead cannot be undone from the API.

Use this when the user wants to permanently delete a leads list, identified by ID. Lists with more than 10 leads are scheduled for asynchronous deletion (HTTP 202). Free to call. Deleting a list cannot be undone from the API.

Use this when the user wants the count of email addresses Hunter has indexed for a domain, optionally split by personal vs generic. Free to call. Do not use this as a substitute for Domain-Search; this returns a count only, not the email list itself.

Use this when the user wants to look up a company by domain and see its industry, size, location, technologies, funding rounds, and social profiles. Does not return personal data (PII). Uses Hunter credits, charged only when data is found. Do not use this for personal websites or webmail domains (gmail.com, yahoo.com, etc.) — there is no company behind those domains to enrich.

Company-Enrichment

Use this when the user wants to look up a professional contact by email address and see their name, job title, employer, location, phone number, and social profiles. Uses Hunter credits, charged only when data is found. Do not use this for consumer profiles — Hunter's enrichment covers business contacts.

Person-Enrichment

Use this when the user provides an email address or LinkedIn handle and wants both the person's profile and their company's profile in a single response. Uses Hunter credits, charged only when data is found. Do not use this when the user only needs one side of the picture — call Person-Enrichment or Company-Enrichment directly to keep the response narrow.

Combined-Enrichment

Use this when the user wants to mark a company list as a favorite, identified by ID. Favoriting is a reversible flag (it can be undone later) and does not change the list's contents. The call is idempotent: favoriting a list that is already a favorite still succeeds and returns `favorited: true`. Surface the `favorited: true` response to confirm the action succeeded. Returns a not-found error if the list does not exist or belongs to another team. Free to call.

Use this when the user wants the contacts published for a domain — emails with names, positions, and confidence scores. Optional filters: type, seniority, department, required field. Uses Hunter credits: 1 credit per 10 emails returned (rounded up), charged only when emails are found. Do not use this for personal/webmail domains (gmail.com, yahoo.com, etc.) — results will be empty.

Domain-Search

Use this when the user wants a specific person's email address at a company. Provide the person's full name and the company's domain. Uses Hunter credits, charged only when an email is found. Do not use this when the user already has the email and only wants to confirm it works — call Email-Verifier instead.

Email-Finder

Use this when the user wants to search for companies that match natural-language criteria such as location, industry, size, type, or technologies. Returns up to 100 matching companies per page; use `offset` to paginate. The response includes `meta.permalink` — a link to the same query on hunter.io that the user can open to view all results with the inferred filters applied. Free to call. Do not use this when the user has already named a specific company — call Company-Enrichment directly with that company's domain.

Use this when the user asks about their Hunter plan or remaining credits. Returns plan name and per-product credit balances (search, verification, enrichment). Does not return personal identifiers such as name, email, or team ID. Free to call.

Use this when the user wants the details of a single company list, identified by ID: its `name`, `type` (static or dynamic), `filters` (for dynamic lists), `company_list_folder_id`, `created_at`, and `companies_count` (the number of companies currently in the list). Returns a not-found error if the list does not exist or belongs to another team. Free to call.

Use this when the user wants the details of a single connected app, identified by ID, including its `attribute_mappings` — the list of `target_field` ↔ `source_field` pairs that map Hunter fields to the integration's fields. Present the mappings as a table or list. Also returns the `provider`, resolved `name`, `category`, `provider_email`, and `connected_at` / `updated_at` timestamps. Returns a not_found error if the app does not exist or belongs to a different team. Free to call.

Use this when the user wants to retrieve a single custom-attribute definition by ID. Free to call.

Use this when the user wants to retrieve a single lead from their Hunter account by ID. Free to call.

Use this when the user wants to retrieve a single leads list (name, lead count, timestamps) by ID. Free to call.

Use this when the user wants to see how a sequence is performing. Reports recipient-based stats for a sequence plus a per-follow-up breakdown. The top-level engagement totals (`sent`, `delivered`, `opened`, `clicked`, `replied`, `unsubscribed_recipients`) count DISTINCT recipients — e.g. `replied` is the number of recipients who replied at least once, not the number of reply messages — and `delivered` is the recipients who received at least one non-bounced email (`recipients_count` is all recipients ever added to the sequence). `bounced` is message-based (a bounce is an SMTP-level event). The rate fields (`open_rate`, `click_rate`, `reply_rate`, `bounce_rate`, `unsubscribed_recipients_rate`) are floats in the 0.0-1.0 range — multiply by 100 to present them as percentages to the user — and are 0 when their denominator is 0; `open_rate`, `click_rate`, and `reply_rate` divide by distinct delivered recipients, while `bounce_rate` is message-based. The `follow_ups` array reports MESSAGE-based metrics per step (ordered by step, then variant; `variant` is null for the default follow-up or A/B for A/B-tested steps), so per-step counts do not sum to the recipient-based top-level totals. Returns a not-found error if the sequence does not exist or belongs to another team. Free to call.

Use this when the user wants to check whether a lead with a given email already exists in their Hunter account. Returns the lead ID and list info if present. Free to call.

Use this when the user wants to list the recipients of a campaign with per-recipient status. Free to call.

Use this when the user wants to list the campaigns in their Hunter account with name, status, and counts. Campaigns are created in the Hunter web UI; the API can list them, manage recipients, and start them. Free to call.

Use this when the user wants to see the company-list folders in their Hunter account. Folders group company lists. Lists are ordered with the most recently created first. Each folder reports its `name`, `color` (a hex color string), `company_lists_count` (how many lists are filed in it), and `created_at`. Folders are visible to the whole team. Supports `limit` and `offset` pagination. Free to call.

Use this when the user wants to see the company lists in their Hunter account. Lists are ordered with the most recently created first. Each list reports its `type` — `static` (a fixed set of companies the user adds manually) or `dynamic` (companies matched automatically by saved `filters`, which are included for dynamic lists) — along with its `name`, `company_list_folder_id` (the folder it lives in, or null), and `created_at`. Surface the `type` for each list, and for dynamic lists mention the `filters` for context. Supports `limit` and `offset` pagination. Free to call.

Use this when the user wants to see the connected apps (third-party integrations such as HubSpot, Pipedrive, Google Sheets, or a custom SMTP/IMAP inbox) linked to their Hunter account. Surface each app's `provider` and resolved `name` clearly: canonical names like Google Sheets come from Hunter's internal catalog, while others fall back to the provider name. Each entry also includes `category`, `provider_email`, and the `connected_at` / `updated_at` timestamps. Supports `limit` and `offset` pagination. Returns an empty list if no apps are connected. To inspect a specific app's field mappings, follow up with Get-Connected-App using its `id`. Free to call.

Use this when the user wants to list all custom attributes defined on leads in their Hunter account. Free to call.

Use this when the user wants to see the email accounts (sending inboxes) connected to their Hunter account, typically as the first step before creating or starting a sequence. Surface each account's `sending_status` clearly: `active` means it is ready to send, `paused` means it is disconnected and will not send until reconnected, and `warming` means it is in ramp-up or warmup and currently sends a reduced volume. Each entry also includes the sender's email, name, daily sending limit, and provider (such as gmail or outlook). Supports `limit` and `offset` pagination. Free to call.

Use this when the user wants to list leads from their Hunter account, with optional filters on email, name, company, or list. Returns up to 100 leads per page; use `offset` to paginate. Free to call.

Use this when the user wants to list the leads lists in their Hunter account, with pagination. Free to call.

Use this when the user wants to see the follow-up steps of a sequence, ordered by step. Step 0 is the introduction message and steps 1 and up are follow-ups; each step reports its `wait_days` (days to wait before sending), `subject` (the email subject; an inherited subject is resolved to the prior step's subject, so it is rarely empty), `body`, `message_format` (text or html), `messages_sent`, and `variant` (null, or A/B for A/B-tested steps). Supports `limit` and `offset` pagination. Returns a not-found error if the sequence does not exist or belongs to another team. Free to call.

Use this when the user wants to move every lead from a source list into a destination list. The source list is permanently deleted after the move. Leads on the destination list are preserved. Free to call. Merging cannot be undone from the API.

Use this when the user wants to pause a started sequence so it stops sending outbound emails until it is resumed. Only a started, non-archived sequence can be paused: pausing a draft (not yet started) or an archived sequence returns an invalid_input error (id sequence_not_active). Pausing an already-paused sequence is idempotent and succeeds. The response reports the sequence id and its paused state — surface that the sequence is now paused and that pausing is reversible. Returns a not-found error if the sequence does not exist or belongs to another user (this endpoint is owner-only). Free to call.

Use this when the user gives a natural-language prospecting brief (e.g. "Find 20 marketing leads at fintech companies in Berlin") and wants a step-by-step plan for finding companies, contacts, verifying emails, and saving leads. Returns the plan plus a first action so the model can execute the chain end to end. Free to call; sub-tools charge their own credits.

Use this when the user wants to remove recipients from a campaign by email address. Pending messages scheduled for the removed recipients are cancelled; messages already sent are not recalled. Free to call.

Use this when the user wants to remove a company from a static company list. Identify the list by `company_list_id` and the company by `company_id`. This removes only the membership link between the company and the list; the company itself is not deleted and can be saved back to the list later, so the action is reversible. The list must be static (dynamic lists manage their members automatically). Succeeds with no content on success. Returns a not-found error if the list or company does not exist, belongs to another team, the list is dynamic, or the company is not in the list, or a forbidden error if the user is not allowed to modify this list. Free to call.

Use this when the user wants to resume a paused sequence so it starts sending outbound emails again. Resuming runs the full validation pipeline (unlike pausing), so it can fail with an invalid_input error: resuming an archived sequence is rejected (id sequence_not_active), and resuming a sequence whose email account is no longer connected or whose schedule has no sending days fails validation (id validation_failed, with a field-specific message) — relay that message to the user so they can fix the configuration. Resuming a sequence that is not currently paused is a no-op that succeeds with the message "Sequence is not paused.". The response carries a `message` describing the outcome — surface it and note that resuming is reversible (pause to stop sending). Returns a not-found error if the sequence does not exist or belongs to another user (this endpoint is owner-only). Free to call.

Use this when the user wants to add a company as a lead in their Hunter account, identified by domain. Free to call.

Use this when the user wants to start an existing campaign, which begins sending real emails to its recipients. The campaign must have a subject, message body, and connected email account configured in the Hunter UI. Free to call. Starting a campaign sends real emails to recipients and requires an explicit user confirmation: the first call returns a confirmation prompt without sending, and only re-issuing with `confirmed: true` actually starts the campaign.

Use this when the user wants to remove the favorite flag from a company list, identified by ID. This only clears the favorite marker; the list and its contents are untouched, and it can be favorited again later. The call is idempotent: unfavoriting a list that is not currently a favorite still succeeds and returns `favorited: false`. Surface the `favorited: false` response to confirm the favorite was removed. Returns a not-found error if the list does not exist or belongs to another team. Free to call.