Types

Types are the categories that organize your capsules. But they're more than folders. Each Type carries guidance that tells AI how to create and interpret capsules of that Type.

GuidanceCopy Anchor Link

The guidance field is where the real power of Symbol lives. It's a set of instructions (up to 5,000 characters) that AI follows when creating or reading capsules of that Type.

For example, a "Solutions" Type might have guidance like:

Include the symptoms observed, relevant error logs, the root cause analysis, and the fix applied. Structure with ### headings for each section.

When you ask an AI assistant to "Save this as a Solution", it reads the Type's guidance and structures the capsule accordingly.

Built-in vs Custom TypesCopy Anchor Link

Symbol comes with a default "General" Type. You can create as many custom Types as you need:

• Solutions: troubleshooting guides with symptoms and fixes
• Decisions: architectural choices with pros, cons, and rationale
• Prompts: reusable prompt templates you can load with get_capsule_by_ref
• Experiments: things you tried, what worked, what didn't

Creating TypesCopy Anchor Link

Types can be created via the Web UI or through MCP using the create_type tool.

Output templatesCopy Anchor Link

A Type with fields can have an output template: the text every capsule of that Type shows when it has no body of its own. The template is written in Markdown and pulls in each capsule's field values with tokens.

TokensCopy Anchor Link

{{field_name}} is replaced by the capsule's value for that field. For a Books Type with author and rating fields:

By {{author}}. Rating {{rating}}/5.

A field with no value is replaced by nothing, so a capsule without a rating would read "By Frank Herbert. Rating /5." Sections fix that.

SectionsCopy Anchor Link

Wrap text that only makes sense when a field has a value in a section: {{#field_name}} opens it and {{/field_name}} closes it. The text inside shows only when that field has a value, and disappears, together with every token in it, when the field is empty.

By {{author}}.{{#rating}} Rating {{rating}}/5.{{/rating}}

A capsule with no rating reads "By Frank Herbert." and one rated 5 reads "By Frank Herbert. Rating 5/5." The same text appears on the capsule page, in what your AI reads, and in search.

• What counts as a value: any text that is not blank, any number (including 0), yes or no, a list with at least one item, a table with at least one row, and an attached picture or file.
• Sections can hold anything: tokens, Markdown, several lines, and other sections. When a section's opening and closing tags each sit on a line of their own, those lines disappear too, so a hidden section leaves no blank line behind.
• Code stays as written: a token or section inside inline code or a code block is shown literally, never filled in.

What is refusedCopy Anchor Link

A Type is not saved, and the reply names what to fix, when its template:

• uses a token or a section for a field the Type does not have (output_template_dangling_tokens), or
• has a section that is never closed, a closing tag with no opening tag, or two sections that overlap instead of one sitting inside the other (output_template_malformed_sections). Close the inner section before the outer one.

Both checks apply when a Type is created and when its fields or template change.