Information extraction transforms unstructured document content into structured
data. As of config v0.6, per-field confidence and geometry (bounding
boxes) are treated as outputs of extraction, not a separate downstream
stage. Their settings live under extraction.confidence.* and
extraction.geometry.*; human-in-the-loop review is configured under the
top-level hitl.* block.
This guide consolidates what used to live across three separate documents
(Customizing Extraction, the Assessment Feature, and Bounding Box Integration)
into one place, reflecting the v0.6 model where extraction produces the value,
its confidence, and its location together.
Extraction mode — how values are pulled from the document: Simple (one inference) or Advanced/agentic (a tool-using agent that can shard, validate, and self-correct).
Confidence mode — how per-field confidence + bounding boxes are produced: separate (a dedicated confidence pass), integrated (confidence rides on the extraction inference), or off.
They combine freely. The tables below give pros/cons and a recommendation; the rest of the guide is the detail.
One Bedrock inference returns the structured result
Strands agent with a structured-output tool; can shard large sections, validate against the schema, and self-correct
Pros
Cheapest & fastest; fewest moving parts; works with every model incl. OpenAI GPT-5.x
Highest accuracy on complex/nested schemas; guaranteed schema compliance; deterministic table parsing for big tables; sharding for long docs; model escalation on validation failure
Cons
No built-in validation/retry; a single huge document must fit one inference (context-overflow / read-timeout risk); weaker on deeply nested structures
More inferences → higher per-doc cost & latency; requires a tool-use model (no OpenAI GPT-5.x); still in preview
Choose when
Most documents; small–medium size; simple/flat schemas; lowest cost matters
Complex/nested schemas, strict validation needs, large documents or big multi-row tables, business-critical accuracy
Rule of thumb: start Simple. Move to Advanced when you hit nested-schema accuracy limits, need schema-format validation, or the document is large enough that one inference can’t hold it (long tables, 20+ dense pages).
A dedicated confidence inference (Simple: the standalone Assessment step; Advanced: one pass inside each shard)
Confidence rides on the extraction inference — no separate pass. Simple uses 1S-TopK (the model returns top-K guesses + probabilities per field); Advanced has the agent emit confidence via its tools
No confidence produced
Inferences added
+1 (Simple) / +1 per shard (Advanced)
0 (Simple, single-shot) / 0–1 (Advanced)
0
Pros
Best-calibrated (a fresh look at finalized values); can use a cheaper model than extraction (default Nova Lite); large lists batched reliably
Fewest inferences → lowest confidence cost; one round-trip on the simple path
Zero confidence cost
Cons
Extra inference(s) → more cost/latency than integrated
On the Simple path everything (context + values + all confidence) must fit one response → truncation risk on large docs/tables; can’t use a separate cheaper model
No confidence → no HITL routing, no UI confidence/threshold signals
Choose when
Default for almost everyone — the calibration and cheap-model economics usually win
Small documents where one inference comfortably holds values and confidence, and you want to minimize round-trips
Confidence genuinely not needed (no HITL, no reliability signal)
Recommended defaults:Simple + separate for most workloads; Advanced + separate for complex or large documents. Reach for integrated only on small docs where minimizing inferences matters, and off only when you don’t consume confidence at all.
Simple + integrated uses 1S-TopK. On the Simple path, integrated mode asks the model for its top-K guesses with probabilities per field (G1/P1 … GK/PK) in one call; the top guess becomes the value and its probability the confidence. Enumerating alternatives yields better-calibrated, less-overconfident scores than a single value + a single confidence number (Tian et al., “Just Ask for Calibration”, EMNLP 2023). The output result.json is identical in shape to separate mode (same inference_result + explainability_info), so HITL, evaluation, reporting, and the UI are unchanged, and the standalone Assessment step auto-skips. The prompt is editable in the UI (“Task prompt (1-Stage TopK extraction + confidence — simple)”) / extraction.task_prompt_extraction_with_confidence_topk. See the reference config and the extraction library README.
Large lists & truncation are handled on every path. Whichever combination you pick, long list fields are assessed in sequential batches (list_batch_size), and if the confidence model truncates a batch at its output-token ceiling the batch is recursively split until it fits — so you get complete per-cell coverage without tuning. See Large-list batching. For documents that are large because of a very large single section (not just a long list), prefer Advanced sharding — see Large-Document Guidance.
Simple extraction sends the system prompt and task prompt to Bedrock in a single
inference and parses the structured (JSON or YAML) response. It is the default
and is a good fit for the majority of documents.
extraction:
agentic:
enabled: false# Simple mode (default)
model: anthropic.claude-3-haiku-20240307-v1:0
temperature: 0.0
reasoning_effort: low# reasoning-capable models only (see note below)
Output tokens: extraction and the confidence pass always request the
selected model’s maximum output — there is no max_tokens config knob for
them. Bedrock’s default-when-omitted truncates, so the client sets it
explicitly from the per-model limits (seeded from
config_library/model_config_limits.yaml and editable in the web UI under
View / Edit Model Limits); completeness matters more than an output cap
here. (classification / summarization keep their max_tokens knob.)
Reasoning effort: for reasoning-capable models — Claude Sonnet 5 / Sonnet
4.6 / Opus 4.5–4.8 / Fable 5 (low|medium|high|xhigh|max) and OpenAI
GPT-5.x (minimal|low|medium|high) — reasoning_effort controls how much
the model reasons before answering. Extraction defaults to low: a full
effort sweep found higher effort adds output-token cost with negligible
extraction-accuracy gain. Raise it per-config for reasoning-heavy documents.
Ignored by Nova, Sonnet 4.5, and Haiku 4.5.
Advanced (agentic) extraction uses the Strands agent framework with tools for
structured output, giving superior accuracy and consistency — especially for
complex documents with nested structures or strict schema requirements. It
shards large sections and runs both extraction and confidence assessment
per shard.
Preview Status: Agentic extraction is currently in preview. While it
demonstrates significant improvements in accuracy and reliability, we
recommend thorough testing in your specific use case before production
deployment.
When to enable agentic extraction — when you need:
Schema Compliance: Guaranteed adherence to defined data structures
Data Validation: Automatic validation with retry mechanisms
Complex Structures: Proper handling of nested objects and arrays
Date Standardization: Consistent date formatting
Self-Correction: Automatic fixing of extraction errors
Production Reliability: Higher accuracy for business-critical data
Extensibility: Future integration with Model Context Protocol (MCP) servers for advanced validation, enrichment, and external data lookups during extraction
Agentic extraction requires models with tool-use support:
Anthropic Claude Sonnet models (recommended for optimal performance)
anthropic.claude-3-5-sonnet-20241022-v2:0 — Best balance of speed and accuracy
anthropic.claude-3-7-sonnet-20250219-v1:0 — Latest with enhanced capabilities
Anthropic Claude Opus models (for highest accuracy requirements)
Amazon Nova Pro (AWS native alternative)
Amazon Nova Premier (for complex multi-modal extraction)
⚠️ OpenAI GPT-5.x cannot be used with agentic extraction.openai.gpt-5.4
/ openai.gpt-5.5 run on the bedrock-mantle Responses API and do not support
the Converse-based Strands agent loop. Pairing an OpenAI model with
extraction.agentic.enabled: true is a hard error in
idp-cli config-validate and raises at runtime. OpenAI models are fully
supported for Simple (non-agentic) extraction. See
OpenAI GPT-5.x Models.
Agentic extraction may have slightly higher costs due to additional processing
for validation and correction, tool-use requiring more capable models, and
retry attempts. The benefits typically outweigh the costs: agentic extraction
improves model performance significantly — for example, Claude Sonnet 3.5 gains
over 20% in accuracy on the getomni-ai benchmark.
100% schema compliance vs frequent validation failures
Reduced manual review and correction efforts
Automatic caching: For supported models, prompt and tool caching is automatically enabled, reducing costs for repeated extractions with the same configuration
How agentic uses your configuration: Agentic extraction automatically
converts your document class configuration (classes, attributes, descriptions,
types) into Pydantic models internally. Improving your configuration directly
improves extraction accuracy. A future enhancement will let you define custom
Pydantic models with validators, custom types, and business logic — including
MCP server integration for real-time external lookups.
For documents with large tables (bank statements, brokerage holdings,
transaction logs), enable the deterministic table parsing tool so the agent
extracts tabular data by parsing Markdown tables directly from OCR — instead of
having the LLM regenerate every row (slow, costly, and error-prone for hundreds
of rows):
extraction:
agentic:
enabled: true
table_parsing:
enabled: true# give the agent a deterministic parse_table tool
min_parse_success_rate: 0.90# below this, fall back to LLM extraction
max_empty_line_gap: 3# tolerate page-break gaps inside a table
auto_merge_adjacent_tables: true
lazy_images: true# skip pre-loading page images when the table
# parse succeeds (big cost saver; see below)
lazy_images (default true) — cost optimization for table documents. When
a pre-flight table parse succeeds, page images are not attached to the
extraction prompt. The deterministic table tool is text/markdown-driven and never
reads images, and the agent can still fetch a specific page on demand via the
view_image tool. Because the agentic loop re-sends the prompt on every turn,
pre-loaded images are re-transmitted repeatedly and dominate cost on multi-page
documents (and push large documents toward context-window limits). A controlled
A/B measured no change in list completeness or field accuracy with images off on
the table path. Set lazy_images: false for image-dependent corpora where the
model must see page layout/marks even when a table is present.
Requires Markdown tables in the OCR output. Table parsing only engages when
OCR emits Markdown pipe-tables — i.e. Amazon Textract with the TABLES
feature enabled (keep LAYOUT + TABLES in ocr.features), or another OCR
backend that produces Markdown tables. With plain-text OCR the agent falls back
to LLM extraction (use sharding, below, for large tables in that case).
Agentic extraction can validate its output against the full class JSON
Schema — including format keywords (date, email, uuid, …) that
type-checking alone misses — and, on failure, escalate the failing fields to a
stronger model:
escalation_model: "us.anthropic.claude-opus-4-8"# stronger tier; blank = retry same model
min_population_ratio: 0.5# advisory: warn if <50% of fields populated (silent-loss guard)
fail_action: escalate re-extracts only the failing top-level fields with escalation_model and merges them back (kept only if valid or fewer errors) — far cheaper than human review. warn records the outcome and proceeds; reject marks the section failed for HITL.
A per-class override x-aws-idp-extraction-escalation-model takes precedence over the global escalation_model.
min_population_ratio is an advisory completeness heuristic: it flags suspiciously sparse results (e.g. a table that returned zero rows) without failing extraction.
Outcomes are recorded per section under metadata.validation and metadata.population_check, and surfaced in the Web UI Processing Report tab.
format: date caveat. JSON-Schema format: date means ISO-8601
(YYYY-MM-DD). The default extraction prompt asks the model for MM/DD/YYYY,
which will fail format validation — set check_formats: false or use a
pattern for non-ISO dates.
Scalable extraction for large documents (sharding)
For long or dense documents, agentic extraction shards a section’s pages into
token- and page-budgeted ranges and extracts them concurrently, then merges the
results (list rows concatenated in page order; scalars resolved first-non-null).
This bounds each agent’s context — preventing read-timeout / context-overflow
failures a single huge request would hit — and runs shards in parallel.
“Shard,” not “chunk.” A shard is a non-overlapping page range handed to
one concurrent extraction agent — the term carries the distributed-systems
sense of partitioning for parallelism. It is intentionally distinct from
chunking, which elsewhere in IDP means overlapping text windows (RAG-style)
or sequential list sub-batches; shards do not overlap and run in parallel.
extraction:
context_buffer: 0.30# ONE knob: keep 30% of each model window free (auto-sizes everything below)
agentic:
enabled: true
runtime: step_functions# DEFAULT for agentic: per-shard Lambdas defeat the 900s timeout + resume
shard_token_budget: 0# 0 = AUTO-size from the model's context window (minus context_buffer)
max_pages_per_shard: 5# page ceiling per shard (timeout-critical; fixed default, not model-derived)
Model-aware auto-sizing (default).shard_token_budget: 0 means the per-shard OCR-token budget is derived from the extraction model’s context window minus context_buffer — a 1M-context model (:1m) shards much larger than a 200K one, automatically. The confidence list-batch size is likewise auto-derived from the confidence model’s output cap. You set only context_buffer; the derived sizes are logged and shown in the Processing Report. Non-zero values pin an explicit override.
max_pages_per_shard is the timeout lever. It stays a small fixed default (5) rather than model-derived: the 900s Lambda limit is about sequential agent turns per shard (wall-clock), not context tokens, so a roomy token budget must not collapse a large doc back into one giant shard. Fewer pages/shard ⇒ fewer turns ⇒ each shard Lambda finishes well under 900s.
Advanced defaults to the resumable runtime.runtime: step_functions is now the agentic default: each shard is its own Lambda iteration in a nested Step Functions Distributed Map, so a very large section is not bound by the single-Lambda 15-minute limit and Step Functions retries only the incomplete shards (completed shards are reused from S3). in_process (asyncio within one Lambda) remains available but is still bound by that one Lambda’s 900s.
Confidence and bounding-box grounding are sharded too. Each shard runs its confidence assessment and grounds its own rows’ bounding boxes against only its own pages — so both scale per-shard and run concurrently. The final merge only concatenates already-scored, already-grounded rows (plus a fast top-up for any rows the assessment LLM omitted); it does not re-assess or re-ground the whole section. This keeps the merge step fast even on very large tables (previously a single full-section grounding sweep over thousands of rows could approach the merge Lambda’s 900s limit).
Large-document guidance. The defaults above are tuned to work out-of-the-box on large documents. Validated at scale on 100- and 200-page single- and multi-table documents (exact row counts, no loss/duplication, no timeouts).
See Large-Document Guidance for choosing between
Simple + separate confidence and Advanced sharding.
description: "A billing document listing items/services, quantities, prices, payment terms, and transaction totals"
properties:
InvoiceNumber:
type: string
description: "The unique identifier for this invoice, typically labeled as 'Invoice #', 'Invoice Number', or similar"
InvoiceDate:
type: string
description: "The date when the invoice was issued, typically labeled as 'Date', 'Invoice Date', or similar"
DueDate:
type: string
description: "The date by which payment is due, typically labeled as 'Due Date', 'Payment Due', or similar"
The solution ships predefined attributes for common document types (Invoices,
Forms, Letters, Bank Statements, etc.). You can add or edit attributes through
the Web UI: Configuration → Extraction Attributes tab → select class → Add New
Attribute (name, display name, description, optional formatting hints).
By default all classes use extraction.model. Override on a per-class basis with
x-aws-idp-extraction-model — useful when certain document types benefit from a
different model. The override works with both Simple and Advanced modes; classes
without it continue to use the global model.
extraction:
model: us.amazon.nova-pro-v1:0# Default for most classes
By default every class uses the global extraction.system_prompt and
extraction.task_prompt. Override either (or both) per class with:
x-aws-idp-extraction-system-prompt — overrides the system prompt for that class.
x-aws-idp-extraction-task-prompt — overrides the task prompt for that class.
This is useful when individual classes were independently optimized (e.g. via
separate AutoTune runs). Because the pipeline classifies first and extracts
per-class, the extraction step always knows which class it is processing. Classes
without these extensions use the global prompts. The override task prompt
supports the same placeholders: {DOCUMENT_CLASS},
{ATTRIBUTE_NAMES_AND_DESCRIPTIONS}, {FEW_SHOT_EXAMPLES}, {DOCUMENT_TEXT},
{DOCUMENT_IMAGE}, <<CACHEPOINT>>.
extraction:
model: us.amazon.nova-pro-v1:0
system_prompt: "You are a document extraction assistant."
task_prompt: |
Extract fields from this {DOCUMENT_CLASS} document:
x-aws-idp-extraction-system-prompt: "You are an expert W2 tax form data extractor."
x-aws-idp-extraction-task-prompt: |
Extract the following attributes from this {DOCUMENT_CLASS} form:
{ATTRIBUTE_NAMES_AND_DESCRIPTIONS}
Document text: {DOCUMENT_TEXT}
type: object
properties:
employee_name:
type: string
description: "Employee name"
Note: These overrides also compose with
extraction.custom_prompt_lambda_arn. When a custom prompt Lambda is
configured, the per-class prompts are resolved first and passed to the Lambda
as defaults; any prompts the Lambda returns still take final precedence.
enabled: true# Advanced mode recommended for production
model: anthropic.claude-3-5-sonnet-20241022-v2:0
temperature: 0.0# Keep low for consistency
top_p: 0.1
top_k: 5
reasoning_effort: low# reasoning-capable models only; output is always model-max
system_prompt: |
You are an expert in extracting structured information from documents.
Focus on accuracy in identifying key fields based on their descriptions.
For each field, look for both the field label and the associated value.
When a field is not present, indicate this explicitly rather than guessing.
task_prompt: |
Extract the following fields from this {DOCUMENT_CLASS} document:
{ATTRIBUTE_NAMES_AND_DESCRIPTIONS}
<few_shot_examples>
{FEW_SHOT_EXAMPLES}
</few_shot_examples>
<<CACHEPOINT>>
Here is the document to analyze:
{DOCUMENT_TEXT}
Format your response as valid JSON:
{
"field_name": "extracted value",
...
}
How prompts apply in each mode. Both modes use the same system_prompt and
task_prompt configuration; they are applied differently under the hood:
Simple:system_prompt is the Bedrock system message; task_prompt is the user message with document content; the model responds with JSON/YAML text that is parsed. No validation or retry.
Advanced (agentic):system_prompt is passed via custom_instruction and appended to the agentic system prompt; task_prompt is sent as the user message (text/images as content blocks); the agent returns a validated Pydantic model with automatic retry and self-correction.
You do not need separate prompts for agentic extraction — the better you define
your classes and attributes, the more accurate agentic extraction becomes.
If a document class is marked with x-aws-idp-exclude-from-processing: true (see
Excluding Static Pages in the Classification docs),
ExtractionService.process_document_section short-circuits for any section
classified as that class: no prompt is built and no LLM call is made. A
small stub result.json is written so downstream stages behave exactly as they
would for a real section:
"message": "Section 1 classified as 'PassportApplicationInstructions' ..."
}
section.extraction_result_uri is set to the stub URI. The stub is produced by
idp_common.section_exclusion.build_skipped_stub_result and written by
idp_common.section_exclusion.write_skipped_stub. Confidence assessment also
short-circuits for excluded sections (no LLM call, no additional stub — the
extraction stub is authoritative). See the demo at
notebooks/usecase-specific-examples/ds11-passport-application/demo.ipynb.
Confidence assessment produces a per-field confidence score (0.0–1.0) and an
explanatory reason for each extracted attribute, so you can gauge the reliability
of automated extractions and route uncertain fields to human review. In v0.6 it
is configured under extraction.confidence.
Per-attribute scoring: Individual confidence scores for each field, recursively for nested groups and list items. To keep responses compact, the default prompts ask the model to include a confidence_reasononly for lower-confidence leaves (below 0.9) — a high-confidence value emits just {"confidence": <score>}. This cuts assessment output tokens substantially (output tokens dominate assessment cost) without affecting the scores or thresholds. Widen or remove the threshold in the confidence task_prompt if you want a reason on every field.
Multimodal analysis: Optionally combines OCR text with document images.
Token-optimized: Uses condensed OCR text confidence data for 80–90% token reduction versus full OCR results.
Large-list batching: Long list fields (hundreds of rows) are automatically assessed in sequential batches (list_batch_size) so every row is scored — see below.
UI integration: Results appear in the web interface with color-coded confidence indicators and (with geometry) bounding-box overlays.
extraction.confidence.mode controls where per-field confidence and bounding
boxes are produced. For pros/cons and a recommendation, see
§0 Choosing a configuration; the table
below is the mechanical reference for where each combination runs:
confidence.mode
Extraction mode
Where confidence runs
Standalone Assessment step
separate (default)
Simple (non-agentic)
the standalone Assessment step
runs
separate
Advanced (agentic)
a second inference inside each extraction shard
bypassed (skip)
integrated
Simple (non-agentic)
the single extraction inference itself, in one pass
bypassed (skip)
integrated
Advanced (agentic)
within the extraction agent’s turn (see strategy note)
mode: separate# off | separate (default) | integrated
model: us.amazon.nova-lite-v1:0# default; far cheaper for the confidence pass
temperature: 0.0
top_k: 5
top_p: 0.1
reasoning_effort: low# only used if a reasoning-capable model is selected here
list_batch_size: 25# rows per assessment batch for large lists
system_prompt: |
You are an expert document analyst specializing in assessing the confidence
and accuracy of document extraction results.
task_prompt: |
# ... see prompt placeholders below
Behavior when disabled (enabled: false or mode: off): the assessment
Lambda is still invoked (minimal overhead) but returns immediately with logging
“Assessment is disabled via configuration” — no LLM calls, no S3 operations.
Defaults to enabled when the property is missing.
Migration note: The previous IsAssessmentEnabled CloudFormation parameter
has been removed in favor of this configuration-based control.
Confidence does not have to run as a separate downstream step:
separate on the agentic path runs a second inference inside each extraction shard (over that shard’s pages and extracted values) and collates on merge — per-field, page-ordered for list items, first-shard-wins for scalars — then grounds once in OCR geometry over the whole section. This reuses the sameAssessmentService.assess_results core and ground_assessment_geometry the standalone step uses, so the explainability_info output is identical; only the execution location differs. A single post-merge assessment would re-introduce exactly the context-window pressure sharding removes, hence per-shard.
integrated on the simple path is a true single inference: one Bedrock call returns values and confidence together. The prompt asks for a {"extraction": {...}, "confidence": {...}} envelope; the service splits that (values → inference_result, confidence → explainability_info after threshold-enrichment + OCR grounding), so the standalone Assessment step auto-skips (the single-inference cost win). For robustness the split also recognizes a field_assessment (or confidence) sibling key placed next to the extracted fields — a shape some models emit — and lifts it the same way (and strips it from inference_result so it never leaks). Only a genuinely flat response with no recognizable confidence falls back to the standalone step. Best for smaller documents where the whole doc fits one inference; for large docs prefer agentic or separate. Any list rows the single inference leaves unscored are retried (missing rows only, bounded) so large-list coverage still reaches 100%.
integrated on the agentic path produces confidence within the agent’s turn. Because extraction is delivered through a tool call, a hidden experimental setting extraction.agentic.integrated_confidence_strategy controls how confidence is produced. It is deliberately not exposed in the config UI; set it via idp-cli config-upload on a throwaway config version to A/B the trade-off. Both values yield identical explainability_info:
two_step(default): the agent extracts, then calls provide_field_assessment in a follow-up inference — a dedicated reflection pass over finalized values (often better-calibrated). ~3 inferences: extract → assess → close.
single_shot: the agent emits values and per-field confidence in one combined tool call, saving the middle inference. ~2 inferences. Multi-step (patched) extractions may still call provide_field_assessment once at the end so every row is assessed (unassessed rows padded with neutral confidence: null).
Both reuse the same prompt cache, so the saving from single_shot is one fewer inference, not a change in cached-token economics.
Automatic bypass of the standalone step. When extraction has already written
explainability_info to the section result, the Assessment Lambda’s intelligent
skip detects it and returns immediately without a second LLM call — no duplicate
cost and no state-machine change is required. The document status stays
EXTRACTING while in-shard assessment runs.
For documents with large lists (bank statements with hundreds of transactions,
line-item tables, brokerage holdings), a single confidence inference over the
whole section under-enumerates or omits the list, leaving most rows unassessed.
Every confidence path batches large lists automatically — the standalone
Assessment step (Simple + separate), the in-shard pass (Advanced + separate),
and the inline-confidence retry (integrated) all share one implementation:
It slices the largest list field into extraction.confidence.list_batch_size
chunks (default 25).
Each chunk is assessed sequentially, sharing the scalars/context.
The concatenated per-row assessments are reconciled so every list cell
receives its own confidence and (in an OCR-backed geometry mode) its own
bounding box.
So large lists are handled with no extra configuration regardless of the
Simple/Advanced or separate/integrated choice. The one knob is list_batch_size
— lower it if a model still struggles to enumerate a full chunk; raise it
to reduce the number of inference calls.
extraction:
confidence:
enabled: true
mode: separate# separate (default) | integrated | off
list_batch_size: 25# rows per assessment batch for large lists
Automatic recovery when the model truncates (self-healing).list_batch_size
is a row count, but the model’s real limit is its max output tokens. When
per-row output is large — most notably with geometry.mode: llm/llm_grounded
(a bounding box per cell, ~3× the output) — a batch can overflow a small-cap
model’s ceiling (e.g. Amazon Nova Lite caps at 10,000 output tokens). A
truncated response is unparseable, which used to silently assign a default
0.5 to every field and leave list rows unscored. Advanced mode now heals this
automatically, cheapest-first:
Token-aware first-pass sizing. The first batch is sized to the confidence
model’s output cap — so Nova Lite + llm_grounded starts at ~6–9 rows
instead of truncating at 25. This only ever shrinkslist_batch_size; a
large-output model keeps your configured size.
Recursive splitting. Any batch that still truncates is halved and
re-assessed until it fits.
Model escalation. If rows are still unscored after shrinking + retries,
the remaining rows are re-assessed on a stronger confidence model (bigger
output cap). ON by default; configure with:
Per-class override: x-aws-idp-confidence-escalation-model. Set
escalation_model: null to skip the model step.
This activity is recorded in the section’s
metadata.assessment_batch_split_stats (derived_batch_size,
escalation_model, rows_recovered_by_escalation, unrecoverable_rows, …) and
(for agentic) an ⚠ Assessment Batch Splitting block in the processing report.
If rows remain unscored even after escalation, the durable fix is to reduce
per-row output — e.g. set geometry.mode: ocr_only (the default) so boxes come
from OCR value-matching rather than the model.
Surfaced in the UI. Whatever the self-healing ladder does (or can’t do) is
recorded as a structured processing issue on the section — severity
(error / warning / info), code (e.g. assessment_incomplete,
assessment_recovered_with_retries, assessment_deadline_reached), a
user-facing message, and a technical root_cause. These are persisted to
DynamoDB and shown in the Web UI: a Status column on the document’s Sections
panel (hover for the message + root cause), a Processing Issues count column
on the document list, and a structured list at the top of the section
Processing Report tab. A document that quietly self-healed — or one where a
row genuinely couldn’t be scored — is therefore visible at a glance.
This replaces granular assessment. The former “granular assessment”
service (a separate thread-pool fan-out with DynamoDB caching) has been
retired and deleted. Large-list batching is its full replacement: complete
per-cell confidence and geometry at roughly −78% Bedrock cost on a 120-row
bank statement, with equal accuracy (granular actually produced 0% geometry).
Any legacy granular.* keys still validate but are ignored — no config edit is
required. See Granular Assessment Retirement.
For very large or complex documents, prefer Advanced (agentic)
extraction — it shards both extraction and assessment and produced the
best-calibrated confidence in A/B testing. Simple + separate remains fully
viable for large lists via the batching above. See
Large-Document Guidance.
Geometry gives each extracted field a bounding box locating it in the
document, which the Web UI renders as an overlay linking form fields to their
place on the page. Geometry is an output of extraction, configured under
extraction.geometry. The UI-compatible geometry format matches BDA mode:
geometry is an array of { boundingBox: {top, left, width, height}, page }
with normalized 0–1 coordinates and 1-based page numbers, supporting nested
group attributes and list items recursively.
extraction.geometry.mode controls where field bounding boxes come from:
geometry.mode
Source of boxes
Notes
ocr_only(default)
Real OCR lines only
Model is not asked for boxes; cheapest and most accurate
llm_grounded
LLM estimates, grounded in OCR
Model emits boxes; service replaces them with real OCR boxes where the value matches
llm
LLM estimates as-is
Escape hatch; no grounding
off
None
No geometry produced
extraction:
geometry:
mode: ocr_only# ocr_only (default) | llm_grounded | llm | off
task_prompt_bbox: |# only used by llm_grounded / llm modes
# ... spatial-localization guidelines (see below)
v0.6 rename. The LLM-box modes were previously llm_with_ocr_grounding /
llm_only, and the legacy assessment.ground_geometry_in_ocr: false maps to
llm. Old configs are migrated on read.
ocr_only (default) — OCR grounding via pageData.json
In ocr_only mode the model is not asked for boxes at all. Each field’s
geometry is derived by matching the extracted value text against real OCR lines
in the consolidated pageData.json artifact (Amazon Textract, or the Mistral OCR
LambdaHook). This is cheaper (no bbox tokens in the response) and more
accurate (OCR boxes beat LLM-estimated boxes, which models frequently
hallucinate). A field with no OCR match simply has no geometry (geometry is
advisory).
Repeated values are disambiguated by row order — when the same value appears
on multiple rows (e.g. a repeated amount in a table), the i-th assessed list item
maps to the i-th occurrence in reading order.
Format-aware matching. Extraction often canonicalizes a value to a schema
format that differs from how it appears in the document (a date extracted as
2022-04-04 but printed 04/04/2022; an amount 1234.00 printed $1,234.00; a
phone +15551234567 printed (555) 123-4567). Matching is bridged three ways:
Format variants — the value is re-rendered in common surface forms and each is matched.
Type-aware equality — value and OCR line are parsed as the same logical date/number/phone and compared (robust to any rendering).
Character-level Levenshtein — last resort for OCR noise (e.g. Acme vs Acrne).
The field’s logical type comes from its JSON-Schema type/format when present,
else inferred from the value. Format-bridged matches are tagged
geometry_source: "ocr-normalized" and Levenshtein near-misses "ocr-fuzzy",
distinct from exact "ocr" hits so they stay auditable.
- Make bounding boxes tight around the actual text content
</spatial-localization-guidelines>
Provide confidence assessments with spatial localization in JSON:
{
"attribute_name": {
"confidence": 0.85,
"confidence_reason": "Clear text with high OCR confidence",
"bbox": [100, 200, 300, 250],
"page": 1
}
}
Automatic coordinate conversion. When the LLM returns bbox data, the service
automatically detects bbox/page, converts from the 0–1000 normalized scale to
0–1 decimals, transforms [x1, y1, x2, y2] into {top, left, width, height},
and processes nested/list attributes recursively. Reversed coordinates are
auto-corrected; invalid or incomplete boxes are dropped (confidence assessment
continues).
llm_grounded: the LLM box is grounded in real OCR coordinates where the value matches, falling back to the LLM box otherwise. The LLM box also disambiguates repeated values by spatial proximity.
llm: the model’s boxes are used as-is with no grounding.
For ocr_only and llm_grounded, grounding is a post-LLM, server-side
enrichment step (it does not change the prompt or its token budget). After
extraction/assessment, the service reads the consolidated per-page
pageData.json directly from
S3 and matches each extracted value to an OCR line.
For each assessed leaf field, the service:
Loads pageData.json for the section’s pages via Page.ocr_page_data_uri (older documents without this artifact are skipped — see fallback).
Matches the value against the page’s OCR lines[], in precision order: exact line → value contained in a line → multi-line span (boxes unioned) → single-line fragment → token-overlap fuzzy (Jaccard ≥ 0.6).
Disambiguates repeated values spatially (for llm_grounded): all candidates are collected and the one whose box center is nearest the LLM-estimated box is chosen. Without a usable LLM reference box, an ambiguous match keeps the LLM box rather than risk attaching the wrong row’s geometry.
On a confident match, replaces the field’s geometry with the real OCR box and adds provenance keys.
Output additions on grounded fields:
{
"account_number": {
"confidence": 0.95,
"confidence_reason": "Clear text with high OCR confidence",
geometry_source — "ocr" (grounded in a real OCR line), "ocr-paragraph" (grounded in a paragraph-level box shared by sibling lines, as the Mistral hook produces), "ocr-normalized" / "ocr-fuzzy" (format-bridged / Levenshtein matches), or "llm" (kept the LLM-estimated box).
ocr_confidence — the matched OCR line’s confidence (0–1), when available. Informational only; the LLM confidence/confidence_reason are never overwritten, so HITL triggering and threshold alerts are unaffected.
Safe fallback (backward compatibility). Grounding degrades to exactly the
prior LLM-only behavior — the worst case is no change:
No pageData.json (older documents, or a missing URI) → keep the LLM box.
OCR backend provides no geometry (plain Bedrock LLM OCR, Chandra hook, none backend; geometryAvailable: false) → keep the LLM box.
Value doesn’t confidently match any OCR line, or repeated values can’t be disambiguated → keep the LLM box.
Because grounding reads pageData.json from S3 (not the prompt), it adds zero
tokens to the request.
Fields whose confidence falls below a threshold can be routed to human review.
HITL is configured under the top-level hitl block in v0.6:
hitl:
enabled: true
confidence_threshold: 0.85# fields below this are flagged for review
Human review integrates confidence scores and geometry so reviewers see exactly
which fields need attention and where they appear on the page. For the full
workflow, the review UI, and Amazon A2I integration, see
Human Review.
Confidence thresholds identify extraction results that may require review.
Thresholds can be set globally or per-attribute, and the UI provides immediate
color-coded feedback. The system automatically adds confidence_threshold values
to the explainability_info based on configuration.
Global threshold — system-wide requirement for all attributes:
{
"explainability_info": [
{
"global_confidence_threshold": 0.85,
"YTDNetPay": { "confidence": 0.92, "confidence_reason": "Clear match found in document" },
⚫ Black: Confidence available but no threshold for comparison
Interface coverage includes the Visual Editor tab (split-pane document image
form editing, bounding-box overlays, recursive nested display, inline editing
with change tracking), the JSON Editor tab, the Revision History tab
(audit trail with field-level diffs), smart filters (low-confidence,
evaluation mismatches, collapsible tree), and nested-data support:
Threshold best practices. Set higher thresholds (0.90+) for critical
financial or personal data; use per-attribute thresholds for different data
types; establish reasonable global defaults (0.75–0.85); start conservative and
tune based on accuracy analysis. Route below-threshold extractions to
Human Review.
Both extraction and confidence prompts support precise control over where
document images appear, using the {DOCUMENT_IMAGE} placeholder.
Without the placeholder: images are automatically appended after the text content.
With the placeholder: images are inserted exactly where {DOCUMENT_IMAGE} appears.
extraction:
task_prompt: |
Extract the following fields from this {DOCUMENT_CLASS} document:
{ATTRIBUTE_NAMES_AND_DESCRIPTIONS}
Examine this document image:
{DOCUMENT_IMAGE}
Text content:
{DOCUMENT_TEXT}
Respond with valid JSON containing the extracted values.
Common patterns: visual-first (image before instructions), verification
(image after text to correct OCR errors), and mixed content (image shows
tables/stamps/signatures the text misses). The placeholder works seamlessly with
few-shot examples. For confidence prompts, images are only processed when
{DOCUMENT_IMAGE} is explicitly present (text-only assessment otherwise) — and
exactly one occurrence is required when present.
Multi-page handling. Images are processed in page order with no image count
limits (following the Bedrock API removal of image count restrictions); documents
of any length are processed without truncation.
Benefits: enhanced accuracy, better table/form handling, improved handwritten
content and visual-only elements (stamps, logos, checkboxes), and OCR-error
verification.
Both extraction and confidence support configurable image dimensions under an
image: sub-block. Empty strings or unspecified dimensions preserve the
original document resolution for maximum accuracy (this is the default and
recommended for critical extraction):
extraction:
image:
target_width: ""# Empty string = no resizing (recommended)
target_height: ""# Empty string = no resizing (recommended)
confidence:
image:
target_width: ""
target_height: ""
Configure specific dimensions when optimizing for performance:
Migration from previous versions. The old behavior defaulted empty strings
to 951x1268 resizing; the current behavior preserves original resolution. To
keep the old behavior, set target_width: "951" / target_height: "1268"
explicitly.
CachePoint caches partial computations to improve performance and reduce costs.
Enable it by placing <<CACHEPOINT>> tags in prompt templates to mark where the
model should cache preceding prompt components:
extraction:
model: us.amazon.nova-pro-v1:0# Must be a CachePoint-compatible model
task_prompt: |
<background>
You are an expert in business document analysis and information extraction.
</background>
<<CACHEPOINT>> # Cache the instruction portion
Here is the document to analyze:
{DOCUMENT_TEXT}
Supported models include:
us.anthropic.claude-3-5-haiku-20241022-v1:0
us.anthropic.claude-3-7-sonnet-20250219-v1:0
us.amazon.nova-lite-v1:0
us.amazon.nova-pro-v1:0
Optimal placement: separate static content (system instructions,
few-shot examples — cacheable) from dynamic content (document text — not
cacheable), placing the tag right before the document text. Cached input tokens
are billed at a reduced cacheReadInputTokens rate (roughly 10× cheaper than
standard input tokens).
The extraction service auto-detects and parses both JSON and YAML LLM responses
via extract_structured_data_from_text(). YAML is more token-efficient (~10–30%
fewer tokens; ~25% typical): no quotes around keys, compact nested syntax,
natural multiline support. All existing JSON prompts continue to work unchanged —
no configuration changes required, with intelligent fallback between formats if
parsing fails.
# JSON response (traditional)
extraction:
system_prompt: "You are a document assistant. Respond only with JSON. Never make up data."
task_prompt: |
Extract the following fields from this {DOCUMENT_CLASS} document and return a JSON object:
{ATTRIBUTE_NAMES_AND_DESCRIPTIONS}
Document text: {DOCUMENT_TEXT}
JSON response:
# YAML response (more token-efficient)
extraction:
system_prompt: "You are a document assistant. Respond only with YAML. Never make up data."
task_prompt: |
Extract the following fields from this {DOCUMENT_CLASS} document and return YAML:
Improve accuracy by providing examples within each document class configuration
(class-specific — only examples from the same class being processed are
included). Use the {FEW_SHOT_EXAMPLES} placeholder in the task prompt:
Function name must start with GENAIIDP- (required for IAM permissions).
Must return valid JSON with system_prompt and task_prompt_content fields.
Available in Pipeline mode (Patterns 2 and 3 historically).
Input payload provides config, prompt_placeholders (DOCUMENT_TEXT,
DOCUMENT_CLASS, ATTRIBUTE_NAMES_AND_DESCRIPTIONS, DOCUMENT_IMAGE as S3 URIs),
default_task_prompt_content, and serialized_document. Required output:
{
"system_prompt": "Your custom system prompt based on document analysis",
"task_prompt_content": [
{ "text": "Your custom task prompt with business logic applied" },
{ "image_uri": "<preserved_placeholder>" },
{ "cachePoint": true }
]
}
Error handling is fail-fast: Lambda invocation failures, invalid response
format, function errors, and timeouts all cause extraction to fail with detailed
messages. Image bytes are never sent (S3 URIs only) to minimize payload size.
Only GENAIIDP-* functions can be invoked (scoped IAM), and all invocations are
logged. For complete examples see notebooks/examples/demo-lambda/README.md and
notebooks/examples/step3_extraction_with_custom_lambda.ipynb.
Advanced (agentic) extraction is generally the better fit. It shards both extraction and confidence assessment into token-/page-budgeted ranges, bounding each inference’s context and preventing read-timeout / context-overflow failures. It produced the best-calibrated confidence in A/B testing. For 100+ page documents prefer runtime: step_functions and raise max_concurrent_batches (e.g. 10). For large tables specifically, enable table parsing (§1) when OCR emits Markdown tables.
Simple + separate confidence still handles large lists via large-list batching (list_batch_size) — full per-cell confidence and geometry with no extra configuration. This is the direct replacement for the retired granular assessment.
Rule of thumb: a document that is large only because it contains a long list (e.g. a 300-row bank statement) is well served by Simple + separate + batching. A document with a very large single section (dense multi-page narrative or multiple large tables) is better served by Advanced sharding, which also splits the extraction work, not just the confidence pass.
Confidence and geometry are appended to extraction results in the
explainability_info format expected by the UI. The format matches the structure
of inference_result, with three attribute shapes:
Simple attributes — a single {confidence, confidence_reason, confidence_threshold, geometry} object.
Group attributes — nested objects, one confidence object per sub-attribute.
List attributes — an array with one confidence object per field per item (assess each item separately, not as an aggregate).
Complete example (all three shapes, with geometry):
Response requirements: match the extraction structure exactly; assess each
list item separately; provide confidence for each sub-attribute of a group; each
assessment includes confidence (0.0–1.0) and optionally confidence_reason;
the system automatically adds confidence_threshold from configuration.
Prefer Advanced (agentic) for production and for complex/nested schemas, strict validation, and large documents/tables.
Write clear attribute descriptions — detail where and how information appears; more specific descriptions yield better extraction (and, in agentic mode, stronger Pydantic validation).
Balance precision vs recall based on whether false positives or false negatives hurt more for your use case.
Optimize few-shot examples — diverse, representative examples covering common variations and edge cases.
Use CachePoint strategically — cache static content, isolate dynamic content, place the tag right before document text.
Optimize image dimensions — original resolution for forms/tables; smaller for simple text at high volume.
Separate classes for very different layouts of the same document type.
Test end-to-end with the full OCR → classification → extraction pipeline.
Choose models by task — Nova Pro for complex few-shot extraction; Claude Haiku for balanced cost; Claude Sonnet for agentic and highest accuracy.
Confidence & geometry
Be specific about high vs low confidence in prompts; include reasoning examples.
Cost management — disable confidence for non-critical classes (enabled: false); start text-only before adding images; monitor token usage.
Model selection — Claude Haiku/Sonnet class models with temperature: 0 for deterministic scoring.
Risk-based thresholds — 0.90+ for critical data, 0.75–0.85 global defaults, per-attribute overrides where needed.
Keep ocr_only geometry (the default) unless you have a specific reason — it is cheaper and more accurate than LLM boxes.
Tune list_batch_size for large lists — lower if a chunk under-enumerates, raise to cut inference count.
Verify extraction.confidence.enabled: true and mode is not off.
Confirm the assessment Lambda deployed successfully.
For agentic + separate/integrated, remember the standalone step is intentionally bypassed (intelligent skip) once extraction writes explainability_info — this is expected, not a failure.
Template errors
Ensure task_prompt is defined.
Validate placeholder syntax; use exactly one{DOCUMENT_IMAGE} when using images ("found N occurrences, but exactly 1 is required").
Validate OCR quality and the {OCR_TEXT_CONFIDENCE} data.
High costs
Monitor token usage in CloudWatch logs.
Prefer text-only assessment; trim unnecessary prompt context.
Use large-list batching (Simple + separate) rather than one oversized inference.
No bounding boxes generated
In ocr_only/llm_grounded, geometry is advisory — a field with no confident OCR match simply has none. Check that OCR provides geometry (geometryAvailable) and that pageData.json exists for the document.
In llm/llm_grounded, confirm the prompt requests bbox/page data and the model returns valid [x1, y1, x2, y2] in 0–1000 scale with 1-based page numbers.
geometry.mode: off produces no geometry by design.
Invalid coordinates
Ensure LLM boxes are in 0–1000 range; reversed coordinates are auto-corrected, malformed ones dropped.
Confidence threshold / UI issues
Verify confidence_threshold values are between 0.0 and 1.0 and present in explainability_info.
Confirm color coding (green/red/black) and nested-data display.
Key metrics to monitor
InputDocumentsForAssessment, assessment_time_seconds, assessment_parsing_succeeded, and token-consumption logs in CloudWatch.