[SHAI-krishna-Dobhal]

Link to Issue or Description of Change

1. Link to an existing issue (if applicable):

• Related: Audit bare throw new Error sites and adopt the typed-errors module (232 throws across 90 files) #807
• Related: feat: Port the typed-errors module (errors/) from adk-python #583

2. Or, if no issue exists, describe the change:

Problem:
#583 added typed errors, but every one of the 340 throw new Error( sites in core/src still throws a bare Error. Callers can only tell failures apart by matching on error.message.

Solution:
Adds issue-807/throw-inventory.md, a Stage 1 inventory sorting every site into: fits an existing type (185), needs one of 6 proposed new types (105), or keep as bare Error (49). It also confirms StaleSessionError isn't needed, lists ~15 rewraps that drop the original error, and proposes a per-area order for Stage 2.

Testing Plan

Documentation only; no code changes. Site count is reproducible with:
git grep -n "throw new Error(" -- 'core/src/**/*.ts' | wc -l → 340 on 934d6bf.

Unit Tests:

• I have added or updated unit tests for my change. (N/A, docs only)
• All unit tests pass locally. (N/A, docs only)

Manual End-to-End (E2E) Tests:

N/A, docs only.

Checklist

• I have read the CONTRIBUTING.md document.
• I have performed a self-review of my own code.
• I have commented my code, particularly in hard-to-understand areas. (N/A)
• I have added tests that prove my fix is effective or that my feature works. (N/A)
• New and existing unit tests pass locally with my changes. (N/A)
• I have manually tested my changes end-to-end. (N/A)
• Any dependent changes have been merged and published in downstream modules.

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[Varun-S10]

Hi @SHAI-KrishnaDobhal, Thank you for raising the PR and putting together the Stage 1 inventory. Could you please move the file under docs/ (instead of root issue-807/), rebase onto latest main, and run npx prettier --write on it?
Meanwhile, we are forwarding your proposed error types and Stage 2 questions to the team for review.
Hi @kalenkevich, Could you please take a look?

[SHAI-krishna-Dobhal]

@Varun-S10! Done:

• Moved the inventory to docs/issue-807-throw-inventory.md
• Rebased onto latest main (bb9a49a)
• Ran npx prettier --write on it (--check passes)