Schema comparisons
See which fields, types, or required arguments changed between two versions of a tool definition.
Know what your tools expect Private preview
Catch tool mismatches before the next run.
A proposed contract-checking layer for agent tools. Compare schemas, inspect inputs, and make interface changes visible before they surprise your workflow.
In development. Help shape the first release.
toolfern / workspace
Illustrative preview · sample data
A small change, made visible.
Toolsearch_documents
Changed fieldfilters.project_id
Contractoptional → required
Reviewbaseline pending
A closer look at the planned product
ToolfernOne focused layer. More clarity.
Agent tool contract checksBuilt around real engineering workflowsEarly access by request
01 / The product
A focused tool.
A clearer way forward.
Three capabilities planned for the first release of Toolfern.
Example input checks
Try representative inputs against a proposed contract and inspect the fields that do not match.
Reviewable baselines
Keep an agreed version of a tool interface so later changes have a clear point of comparison.
02 / The workflow
Less guesswork.
More context.
Explore the intended workflow, from the first input to a useful result. This is an interactive concept preview.
STEP 01 OF 03
Bring a tool definition and an example input.
See which fields, types, or required arguments changed between two versions of a tool definition.
STEP 02 OF 03
Compare the interface with its previous baseline.
Try representative inputs against a proposed contract and inspect the fields that do not match.
STEP 03 OF 03
Review the changes before updating your workflow.
Keep an agreed version of a tool interface so later changes have a clear point of comparison.
03 / Good to know
A few details,
before you join.
Does a passing check prove a tool is safe?
No. The planned checks concern interface consistency and sample inputs. They cannot guarantee safe behavior, correct results, or a trustworthy tool provider.
Which tool formats will be supported?
The first version is being scoped around JSON-based tool definitions. Format support and import options are not yet finalized.
How do I get access?
Toolfern is in development. Email us with the kinds of tool definitions you use to discuss the private preview.
Help shape what comes next
Be part of the first chapter.
Tell us about your workflow and what you need from Toolfern. We’re opening conversations with potential early users.