update_frontmatter

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries the burden of behavioral disclosure. It discloses the additive/updating nature and preservation of unspecified fields, but does not cover error cases, prerequisites (e.g., note existence), or side effects on note content beyond frontmatter.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is two sentences, front-loaded with the action, and every sentence adds value. There is no fluff or redundancy.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a simple mutation tool with 2 parameters and no output schema, the description covers the core behavior sufficiently. It omits return value/error information, but this is common for write operations and does not severely impact understanding.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so parameters are already documented. The description adds meaningful semantics by explaining how the 'properties' parameter behaves (merging, preserving unspecified fields), which helps correct invocation.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states 'Update frontmatter fields in a note' with a specific verb, resource, and scope. It explicitly mentions adding or updating fields, which distinguishes it from related tools like get_frontmatter or update_note.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description clarifies the merge behavior ('Existing fields not specified are preserved'), implying when to use this tool over a full overwrite. It does not explicitly mention alternatives or exclusions, but the context is clear enough for selection.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.