write_journal

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

No annotations provided, so description carries the burden. It mentions 'durable' and 'private' and the return format, but does not disclose side effects like overwrite behavior, permissions, or idempotency, leaving gaps.

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?

Three sentences, no redundant words. The most critical information (purpose, section usage, return type) is front-loaded and concise.

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 write tool with 2 parameters and no output schema, the description covers purpose, parameter semantics, and return value. It lacks mention of error scenarios but is otherwise adequate.

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?

The schema has 0% description coverage. The description adds the default value for 'section' ('defaults to observations'), which is not in the schema. No additional detail for 'content'. Slight improvement over schema alone.

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 'Write a durable private journal entry' with a specific verb and resource. It distinguishes itself from sibling tools (list, read, search) through the write action.

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?

Provides explicit guidance on when to use alternative sections: 'Use project_notes for repo state, technical_insights for reusable fixes, and user_context for stable preferences.' This helps the agent choose the correct section.

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