This is what a complete results report would look like when each of the fields controlling the output is specified and PDF Checker completes the review successfully.

Note the section at the top of the results output, the CHECKER_SUMMARY.

This is a summary list of the items that PDF Checker found when reviewing a PDF document, intended to be machine readable.

You could set up a batch process to review a set of PDF documents stored in a server directory automatically, one by one. Then, you could add a step to your batch code that would identify the PDF documents that PDF Checker found with issues or problems, create an input JSON file listing those issues or problems, and send that JSON file list to PDF Optimizer.  PDF Optimizer could then optimize each PDF document based on the items found by PDF Checker. Note that for documents that PDF Optimizer can improve, a statement appears, “canBeOptimized,” to make it easy detect documents that are candidates for optimization. The software also provides the size of the PDF source document, and a machine readable value, “sizeInBytes.” This allows you to scan the results to make decisions on document processing based on file size. For example, a PDF document that is only 10 KB probably isn’t worth optimizing.

PDF Checker 1.5.0  Copyright 2018-2019 Datalogics, Inc. All Rights Reserved

Tue Oct 15 17:40:57 2019

JSON Profile: everything.json

Input Document: DocumentationExample.pdf

File Size: 4.2 MB

<<=CHECKER_SUMMARY_START=>>
userdata:contains-annots
userdata:contains-annots-not-for-printing
userdata:contains-annots-not-for-viewing
userdata:contains-embedded-files
userdata:contains-metadata
userdata:contains-transparency
fonts:uses-base14fonts-not-embedded
canBeOptimized
sizeInBytes: 4211884
cleanup:suboptimal-compression
<<=CHECKER_SUMMARY_END=>>

Optimization Assessment
    Document can be optimized with PDF Optimizer – see details below

General Results
    Errors:
        None
    Information:
        None
    Checks Completed:
        claims-pdfa-conformance
        contains-owner-password
        contains-signature
        damaged
        password-protected
        pdf-v2
        unable-to-open
        xfa-type

Userdata Results
    Errors:
        None
    Information:
        Contains annotations: 
            SubType: Circle (1 instance)
            SubType: FreeText (2 instances)
            SubType: Highlight (1 instance)
            SubType: Ink (1 instance)
            SubType: Line (2 instances)
            SubType: Polygon (2 instances)
            SubType: Popup (11 instances)
            SubType: Square (1 instance)
            SubType: Stamp (1 instance)
            SubType: StrikeOut (1 instance)
            SubType: Underline (1 instance)
        Contains annotations that are set as invisible for printing: 
            SubType: Popup (1 instance)
        Contains annotations that are set as invisible for viewing: 
            SubType: Square (1 instance)
        Contains embedded files: 
            Total: (1 instance)
        Contains metadata: 
            SubType: XML, Update region size: 2048 (1 instance)
        Contains transparency: 
            Total: (1 instance)
    Checks Completed:
        contains-annots
        contains-annots-not-for-printing
        contains-annots-not-for-viewing
        contains-annots-without-normal-appearances
        contains-embedded-files
        contains-metadata
        contains-optional-content
        contains-private-data
        contains-transparency
    How To Optimize:
        Annotations can be removed using PDF Optimizer to save space.
        Annotations not intended for printing can be removed using PDF Optimizer to save space.
        Attached files can be removed using PDF Optimizer to save space.
        Metadata can be removed using PDF Optimizer to save space.

Fonts Results
    Errors:
        Uses Base 14 fonts not embedded in document: 
            Helvetica (1 instance)
            Helvetica-BoldOblique (1 instance)
    Information:
        None
    Checks Completed:
        fontdescriptor-missing-capheight
        fontdescriptor-missing-fields
        uses-base14fonts-not-embedded
        uses-fonts-fully-embedded
        uses-fonts-not-embedded

Objects Results
    Errors:
        None
    Information:
        None
    Checks Completed:
        contains-javascript-actions
        contains-thumbnails

Cleanup Results
    Errors:
        None
    Information:
        Contains conservatively compressed streams: 
            Uncompressed: (4 instances)
    Checks Completed:
        suboptimal-compression

Image Results
    Errors:
        None
    Information:
        None
    Checks Completed:
        alternate-images

    Color Images
    Errors:
        None
    Information:
        None
    Checks Completed:
        image-depth
        resolution-too-high
        resolution-too-low
        uses-jpeg2000-compression

    Grayscale Images
    Errors:
        None
    Information:
        None
    Checks Completed:
        resolution-too-high
        resolution-too-low
        uses-jpeg2000-compression

    Monochrome Images
    Errors:
        None
    Information:
        None
    Checks Completed:
        resolution-too-high
        resolution-too-low
        uses-jbig2-compression