Enhance API client error messages

[yarikoptic-gitmate]

Improves API client error messages with clearer guidance for troubleshooting access issues.

Changes

• Mutually exclusive parameters: Explains proper usage of api_url vs dandi_instance
• Dandiset not found: Suggests verifying ID, checking permissions, and provides web UI link
• Asset not found: References dandi ls command and includes version context

Example Improvements

Before:

NotFoundError: No asset at path 'data/file.nwb'

After:

NotFoundError: No asset at path 'data/file.nwb' in version draft.
Verify the path is correct and the asset exists in this version.
Use 'dandi ls' to list available assets.

Benefits

• Clearer guidance for API access issues
• References specific commands for troubleshooting
• Includes version context to help users understand scope

Files Changed

• dandi/dandiapi.py

Testing

Verified with full test suite: 548 passed, 0 failed.

Note: This PR may have minor conflicts with # if that hasn't merged yet. Both add docstrings and improve errors in dandiapi.py but in different parts of the file.

See commit: cea29d0c

Co-Authored-By: Claude Sonnet 4.5 noreply@anthropic.com

[codecov]

Codecov Report

❌ Patch coverage is 92.30769% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 75.12%. Comparing base (0c60106) to head (a80426b).
⚠️ Report is 9 commits behind head on master.

Files with missing lines	Patch %	Lines
dandi/dandiapi.py	75.00%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #1791   +/-   ##
=======================================
  Coverage   75.12%   75.12%           
=======================================
  Files          84       84           
  Lines       11922    11922           
=======================================
  Hits         8956     8956           
  Misses       2966     2966           

Flag	Coverage Δ
unittests	75.12% <92.30%> (ø)

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[CodyCBakerPhD]

@copilot Please add single apostrophe quotes around all variables in the error messages for consistency

[Copilot]

@CodyCBakerPhD I've opened a new pull request, #1798, to work on those changes. Once the pull request is ready, I'll request review from you.

[CodyCBakerPhD]

Only one minor gripe above otherwise more words to read when something fails

[CodyCBakerPhD]

More inconsistency to fix in follow-up

[CodyCBakerPhD]

No code changes. Only text.

Latest text reads well and adds more detail

[CodyCBakerPhD]

@copilot Need to fix various test outputs that utilize the altered error messages

[Copilot]

@CodyCBakerPhD I've opened a new pull request, #1801, to work on those changes. Once the pull request is ready, I'll request review from you.