Openalex Analyze Trends
openalex_analyze_trendsRead-onlyIdempotent
Aggregate OpenAlex entities into groups and count them. Use for trend analysis (group works by publication_year), distribution analysis (group by oa_status, type, country), and comparative analysis (group by institution or topic). Combine with filters to scope the analysis. Returns up to 200 groups per page — use cursor pagination for fields with many distinct values.
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| order | No | Sort order for groups. Omit or pass "count" (default) to return the top-N groups by count descending — no further pages. Pass "key" to enumerate all distinct values in key-ascending order with cursor pagination. Use "key" only when you need a full traversal; most analysis calls want "count". | |
| cursor | No | Pagination cursor from a previous response. Only relevant when order is "key" — count-descending results have no next page. Pass the next_cursor from the previous response to advance. Omit it on the first call — an empty string is rejected, since a supplied-but-blank cursor is a caller mistake rather than a request for the first page. | |
| filters | No | Filter criteria (same syntax as openalex_search_entities filters). Narrows the population before aggregation. For full-text within filters, use abstract.search, title.search, or default.search — there is no bare 'search' filter key. Example: group works by year filtered to a specific topic. | |
| group_by | Yes | Field to group by. Works examples: "publication_year", "type", "oa_status", "primary_topic.field.id", "authorships.institutions.country_code", "is_retracted". Authors: "last_known_institutions.country_code", "has_orcid". Sources: "type", "is_oa", "country_code". Not all fields support group_by — call openalex_describe_fields(entity_type, "group_by") for the groupable set. | |
| per_page | No | Maximum groups per page (1-200). Default 200 (the upstream cap). A real top-N knob when order is count (the default) — reduce to return only the highest-count groups. | |
| entity_type | Yes | Entity type to aggregate. | |
| include_unknown | No | Add a group for entities with no value for the grouped field. Hidden by default. That group carries `is_unknown: true`; OpenAlex keys it -111 or -111.0 on numeric fields, "unknown" on text fields and under order "key", and an ID ending in /unknown on ID fields — a sentinel, not a measured value. The key is not a filter value: passing -111 as a filter matches a numeric range, not the entities with no value. Boolean fields have no separate group — a missing value counts as false. |
Output Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| echo | No | Compact echo of the input criteria (entity_type, group_by, filters) — surfaces what was actually requested when no groups are returned. | |
| meta | No | Aggregation metadata. | |
| error | No | Present when the call failed. Absent on success. | |
| budget | No | What this call cost against the OpenAlex daily budget and what is left of it — weigh `remainingUsd` against `costUsd` before enumerating every group with `order: "key"`. Absent when OpenAlex omitted the accounting headers. | |
| groups | No | Aggregation groups with counts. | |
| notice | No | Guidance notice. Set when a first call returns no groups (recovery suggestions), when a `cursor` continuation returns none because the traversal is already finished, or when the page is full and more groups likely exist (truncation signal with narrowing advice). Absent otherwise. | |
| totalCount | No | Total entities matching the filters before grouping (across all pages). |