Obsidian Bases

Obsidian Bases

Use this as a compact workflow and fallback syntax reference. Prefer a

separately installed kepano/obsidian-skills obsidian-bases skill, then the

current official Bases syntax, for

detailed or version-sensitive fields and functions.

Answer design and syntax questions read-only. For a requested .base edit,

resolve the user vault and use one inspected transaction; never write the file

directly.

Resolve the installed product root from this skill's own location, not from the

vault or current working directory:

PRODUCT_ROOT=/absolute/path/to/installed/claude-obsidian
CORE="$PRODUCT_ROOT/scripts/claude-obsidian.py"
test -f "$CORE"

Workflow

• Inspect representative note properties and any existing .base file.
• Define the smallest filter that selects the intended notes.
• Add formulas only for values that must be computed.
• Choose views and display order. Do not assume a view type or option is

supported by the user's Obsidian version or installed plugins.

• Validate YAML, expression quoting, property names, formula references, and

null handling.

• Preview the complete file and expected result set before a mutation.
• If an edit was requested, read

operation-transactions.md,

keep the .base file under wiki/, and build one

claude-obsidian.transaction.v1 bundle with operation_type: base. Inspect

it, then set APPROVAL_SHA256 to the returned approval_sha256 only after

review and apply once:

   python3 "$CORE" transaction inspect "$BUNDLE" --vault "$VAULT"
   python3 "$CORE" transaction apply "$BUNDLE" --vault "$VAULT" \
     --approved-plan-sha256 "$APPROVAL_SHA256"

• Ask the user to render the Base in Obsidian when application-level behavior

cannot be verified locally.

Compact schema

.base files are YAML. Common top-level keys are filters, formulas,

properties, summaries, and views.

filters:
  and:
    - file.inFolder("wiki")
    - 'status != "archived"'

formulas:
  age_days: '((now() - file.ctime) / 86400000).round(0)'
  status_label: 'if(status == "mature", "Ready", "Review")'

properties:
  status:
    displayName: "Status"
  formula.age_days:
    displayName: "Age (days)"

views:
  - type: table
    name: "Wiki pages"
    order:
      - file.name
      - type
      - status
      - updated
      - formula.age_days

Global filters apply to every view. A view may also define its own filters.

Recursive filter objects use one of and, or, or not at each level.

filters:
  or:
    - file.hasTag("concept")
    - and:
        - file.hasTag("source")
        - 'status == "active"'

Use note properties by name, file metadata as file.name, file.path,

file.folder, file.ext, file.ctime, file.mtime, or file.tags, and

computed properties as formula.<name>.

Formula and YAML rules

• Quote expressions that contain operators, colons, or nested string quotes.
• Guard nullable properties with if().
• Subtracting two dates returns a millisecond number. Divide by 86400000

before rounding when a whole-day count is intended.

• Define every formula.<name> before referencing it in a view or property

display configuration.

• Do not transplant Dataview-only keys such as from or where into a Base.
• Do not invent properties absent from the selected notes without explaining

that the resulting column will be empty.

formulas:
  days_until: 'if(due_date, ((date(due_date) - today()) / 86400000).round(0), "")'

Table, cards, and list views are common:

views:
  - type: cards
    name: "Reading list"
    order:
      - file.name
      - author
      - status
  - type: list
    name: "Quick list"
    order:
      - file.name
      - status

Embed a Base or one named view in a Markdown note:

![[Dashboard.base]]
![[Dashboard.base#Wiki pages]]

After an applied edit, report the operation ID, exact changed path, validation

performed, and anything that still requires rendering in Obsidian. Do not

commit Git.