Primitive Search API
Semantic and hybrid search across received and sent mail
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OpenAPI Specification
openapi: 3.2.0
info:
title: Primitive Search API
version: 1.0.0
description: Primitive is email infrastructure for AI agents.
contact:
name: Primitive
url: https://primitive.dev
license:
name: Proprietary
url: https://primitive.dev/terms
x-stability-level: stable
x-deprecation-policy: 'Breaking changes are announced at least 6 months in advance. Deprecated fields carry x-deprecated: true. The current stable version is v1.'
servers:
- url: https://api.primitive.dev/v1
description: Canonical API host (PRIMITIVE_API_BASE_URL). Carries every public API operation.
tags:
- name: Search
description: Semantic and hybrid search across received and sent mail
paths:
/semantic-search:
post:
operationId: semanticSearch
summary: Semantic search across received and sent mail
description: 'Ranked search across both received and sent mail. The `mode`
field selects the ranking strategy:
- `keyword`: lexical full-text matching only (no embeddings).
- `semantic`: meaning-based matching using vector embeddings.
- `hybrid` (default): blends the semantic and keyword signals.
Results are ordered by a relevance `score`. Every row reports the
fields it matched (`matched_fields`), a match-centered excerpt per
field (`snippets`), and a `score_breakdown` whose components account
for the `score`. Page through results by passing the prior
response''s `meta.cursor` back as `cursor`.
Requires the Pro plan and the `semantic_search_enabled`
entitlement; callers without them receive `403`.
Host routing: this operation is served only by the search host
(`https://api.primitive.dev/v1`). The typed SDKs route it there
automatically.'
servers:
- url: https://api.primitive.dev/v1
description: Search host
tags:
- Search
requestBody:
required: true
content:
application/json:
schema:
type: object
properties:
query:
type: string
minLength: 1
maxLength: 2048
description: 'Free-text query. Required for `semantic` and `hybrid` modes;
optional for `keyword` mode.
'
mode:
type: string
enum:
- hybrid
- semantic
- keyword
default: hybrid
description: 'Ranking strategy. `keyword` is lexical only, `semantic` is
embedding-based, `hybrid` blends both.
'
corpus:
type: array
items:
type: string
enum:
- inbound
- outbound
minItems: 1
maxItems: 2
description: 'Which mail to search. Defaults to both received (`inbound`)
and sent (`outbound`).
'
search_in:
type: array
items:
type: string
enum:
- subject
- headers
- addresses
- body
description: A searchable email field.
description: Restrict matching to these fields. Defaults to all.
exclude:
type: array
items:
type: string
enum:
- subject
- headers
- addresses
- body
description: A searchable email field.
description: Exclude these fields from matching.
date_from:
type: string
format: date-time
description: Only include mail at or after this timestamp.
date_to:
type: string
format: date-time
description: Only include mail at or before this timestamp.
include:
type: array
items:
type: string
enum:
- coverage
description: 'Opt-in extras. `coverage` adds an index-coverage snapshot to
`meta`. Matched fields, snippets, and the score breakdown are
always returned regardless of this field.
'
limit:
type: integer
minimum: 1
maximum: 100
default: 10
description: Maximum number of results to return.
cursor:
type: string
description: Opaque pagination cursor from a prior response's `meta.cursor`.
responses:
'200':
description: Ranked search results
content:
application/json:
schema:
allOf:
- type: object
properties:
success:
type: boolean
const: true
required:
- success
- data
- type: object
properties:
data:
type: array
items:
type: object
properties:
source_type:
type: string
enum:
- inbound_email
- sent_email
description: Whether this row is a received or sent message.
id:
type: string
description: Message id. Combine with `api_url` to fetch the full record.
subject:
type:
- string
- 'null'
from:
type:
- string
- 'null'
to:
type:
- string
- 'null'
timestamp:
type: string
description: Message timestamp (received_at for inbound, created_at for sent).
status:
type: string
description: Lifecycle status of the message.
score:
type: number
description: Overall relevance score; the `score_breakdown` components account for it.
semantic_score:
type:
- number
- 'null'
description: Raw semantic similarity signal, or null when not applicable.
keyword_score:
type:
- number
- 'null'
description: Raw keyword (lexical) signal, or null when not applicable.
matched_fields:
type: array
items:
type: string
enum:
- subject
- headers
- addresses
- body
description: A searchable email field.
description: Fields where the query matched.
snippets:
type: array
items:
type: object
properties:
field:
type: string
description: The field this excerpt came from.
text:
type: string
description: Plain-text excerpt centered on the match (no markup).
required:
- field
- text
description: Match-centered excerpts, one per matched field.
score_breakdown:
type: object
description: 'Additive contributions to `score`. `semantic` and `keyword` are the
raw signals times the mode''s weight (null when not applicable);
these plus `field_boost` and `recency` sum to `score` before each
value is independently rounded to 5 decimal places.
'
properties:
semantic:
type:
- number
- 'null'
keyword:
type:
- number
- 'null'
field_boost:
type: number
recency:
type: number
required:
- semantic
- keyword
- field_boost
- recency
api_url:
type:
- string
- 'null'
description: Relative API path to fetch the full message.
required:
- source_type
- id
- subject
- from
- to
- timestamp
- status
- score
- semantic_score
- keyword_score
- matched_fields
- snippets
- score_breakdown
- api_url
meta:
type: object
properties:
limit:
type: integer
description: Page size used for this request.
cursor:
type:
- string
- 'null'
description: Cursor for the next page, or null if there are no more results.
mode:
type: string
enum:
- hybrid
- semantic
- keyword
description: Ranking mode used for this response.
coverage:
oneOf:
- type: object
description: Index-coverage snapshot for the org, returned only when the `coverage` include option is requested.
properties:
embedded_chunks:
type: integer
pending_chunks:
type: integer
skipped_plan_chunks:
type: integer
skipped_quota_chunks:
type: integer
unsupported_attachment_chunks:
type: integer
failed_chunks:
type: integer
required:
- embedded_chunks
- pending_chunks
- skipped_plan_chunks
- skipped_quota_chunks
- unsupported_attachment_chunks
- failed_chunks
- type: 'null'
description: 'Index-coverage snapshot, present only when requested via
`include: [coverage]`; otherwise null.
'
required:
- limit
- cursor
- mode
- coverage
required:
- data
- meta
headers:
ratelimit-limit:
description: Maximum number of requests allowed in the current window.
schema:
type: integer
minimum: 1
example: 120
ratelimit-remaining:
description: Remaining requests in the current window.
schema:
type: integer
minimum: 0
example: 118
ratelimit-reset:
description: Unix timestamp (seconds) when the current window resets.
schema:
type: integer
example: 1700000060
ratelimit-policy:
description: Rate-limit policy in `limit;w=seconds` format, e.g. `120;w=60`.
schema:
type: string
example: 120;w=60
'400':
$ref: '#/components/responses/ValidationError'
description: Invalid request parameters
'401':
$ref: '#/components/responses/Unauthorized'
description: Invalid or missing API key
'403':
$ref: '#/components/responses/Forbidden'
description: Authenticated caller lacks permission for the operation
'429':
$ref: '#/components/responses/RateLimited'
description: Rate limit exceeded
'500':
$ref: '#/components/responses/InternalError'
description: Primitive encountered an internal error
'503':
$ref: '#/components/responses/ServiceUnavailable'
description: Primitive is temporarily unable to process the request
security:
- BearerAuth: []
parameters:
- name: Idempotency-Key
in: header
required: false
description: Optional client-supplied idempotency key. Retrying a request with the same key returns the original result instead of performing the action a second time; if omitted the server derives one from the canonical payload hash. Safe to retry network failures without duplicating side effects.
schema:
type: string
minLength: 1
maxLength: 255
components:
schemas:
ErrorResponse:
type: object
properties:
success:
type: boolean
const: false
error:
type: object
properties:
code:
type: string
enum:
- unauthorized
- forbidden
- not_found
- validation_error
- rate_limit_exceeded
- internal_error
- conflict
- mx_conflict
- outbound_disabled
- cannot_send_from_domain
- recipient_not_allowed
- outbound_key_missing
- outbound_unreachable
- outbound_key_invalid
- outbound_capacity_exhausted
- outbound_response_malformed
- outbound_relay_failed
- discard_not_enabled
- inbound_not_repliable
- search_timeout
- authorization_pending
- slow_down
- access_denied
- expired_token
- invalid_device_code
- invalid_signup_code
- invalid_signup_token
- invalid_verification_code
- email_delivery_failed
- clerk_signup_failed
- no_orgs_for_user
- org_not_accessible
- feature_disabled
- memory_conflict
- developer_usage_credit_exhausted
- no_payout_address
- ownership_proof_failed
- payment_verification_failed
- payment_declined
- challenge_expired
- settlement_failed
- template_not_installable
- scaffold_only
- invalid_variables
- unknown_secrets
- missing_secrets
- no_inbound_domain
- domain_cannot_send
- address_taken
- route_cap_reached
- name_exhausted
message:
type: string
details:
type: object
description: 'Optional structured data that callers can inspect to recover
from the error. The fields present depend on `code`. Additional
keys may be added over time without a major-version bump.
'
additionalProperties: true
properties:
mx_conflict:
type: object
description: Present when `code == mx_conflict`.
required:
- provider_name
- suggested_subdomain
properties:
provider_name:
type: string
description: Human-readable name of the detected mailbox provider (e.g. "Google Workspace").
suggested_subdomain:
type: string
description: Subdomain to try instead (e.g. "mail" for `mail.example.com`).
required_entitlements:
type: array
items:
type: string
description: Entitlements that would allow a denied send when no recipient-scope gate was granted.
sent_email_id:
type: string
description: ID of the persisted sent-email attempt associated with the error.
content_hash:
type: string
description: Content hash of the original request on idempotency cache-hit errors.
client_idempotency_key:
type: string
description: Effective idempotency key associated with the original request.
gates:
type: array
items:
$ref: '#/components/schemas/GateDenial'
description: Structured per-gate denial detail for recipient-scope send-mail failures.
request_id:
type: string
description: Server-issued request identifier for support and tracing.
required:
- code
- message
required:
- success
- error
GateDenial:
type: object
properties:
name:
type: string
enum:
- send_to_confirmed_domains
- send_to_known_addresses
description: Public recipient-scope gate name that denied the send.
reason:
type: string
enum:
- domain_not_confirmed
- recipient_unauthenticated
- recipient_not_known
description: Stable machine-readable denial reason.
message:
type: string
description: Human-readable explanation of the gate denial.
subject:
type: string
description: Domain or address the gate evaluated.
fix:
$ref: '#/components/schemas/GateFix'
docs_url:
type: string
description: Public docs URL with more context.
required:
- name
- reason
- message
- subject
GateFix:
type: object
properties:
action:
type: string
enum:
- confirm_domain
- sender_must_fix_authentication
- wait_for_inbound
description: Suggested next action for the caller.
subject:
type: string
description: Entity the action applies to.
required:
- action
- subject
responses:
Unauthorized:
description: Invalid or missing API key
content:
application/json:
schema:
$ref: '#/components/schemas/ErrorResponse'
example:
success: false
error:
code: unauthorized
message: Invalid or missing API key
ValidationError:
description: Invalid request parameters
content:
application/json:
schema:
$ref: '#/components/schemas/ErrorResponse'
example:
success: false
error:
code: validation_error
message: Invalid domain format
ServiceUnavailable:
description: Primitive is temporarily unable to process the request
content:
application/json:
schema:
$ref: '#/components/schemas/ErrorResponse'
example:
success: false
error:
code: outbound_capacity_exhausted
message: Outbound capacity is temporarily exhausted
Forbidden:
description: Authenticated caller lacks permission for the operation
content:
application/json:
schema:
$ref: '#/components/schemas/ErrorResponse'
example:
success: false
error:
code: forbidden
message: Insufficient permissions
InternalError:
description: Primitive encountered an internal error
content:
application/json:
schema:
$ref: '#/components/schemas/ErrorResponse'
example:
success: false
error:
code: internal_error
message: Internal server error
RateLimited:
description: Rate limit exceeded
headers:
Retry-After:
schema:
type: integer
description: Seconds to wait before retrying
content:
application/json:
schema:
$ref: '#/components/schemas/ErrorResponse'
example:
success: false
error:
code: rate_limit_exceeded
message: Rate limit exceeded
securitySchemes:
BearerAuth:
type: http
scheme: bearer
description: 'API key with `prim_` prefix or OAuth access token with `prim_oat_` prefix: `Authorization: Bearer <token>`. Access is governed by the caller''s organization role (`owner`, `admin`, or `member`): API keys always act at `member` level regardless of who created them, and OAuth access tokens act with the authorizing user''s current organization role, resolved per request. Every operation in this spec is available to organization members; billing and organization administration are owner/admin actions performed in the dashboard and are not part of this API.'
DownloadToken:
type: apiKey
in: query
name: token
description: Signed download token provided in webhook payloads