sync_reading_history

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

With no annotations, the description carries the full burden and discloses important traits: it fills seen_at and reading progress, never changes a cached post's saved state, stores unsaved viewed posts as is_saved=0, and lists possible status outcomes including auth_required. It is thorough, though it does not cover rate limits, ordering, or full auth requirements beyond the status name.

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 definition is front-loaded with purpose and then adds behavior, parameter meaning, and status values without wasteful sentences. Each sentence contributes relevant context for an unannotated sync tool.

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?

Given one parameter, no annotations, and an available output schema, the description is complete enough for an agent to understand what the tool does, how force changes behavior, what side effects it has on cached data, and what statuses may result.

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 only parameter, force, is explicitly explained: force=True walks the whole history instead of stopping at already-cached views. This meaningfully adds to the schema, which otherwise has no parameter descriptions.

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 states a specific verb and resource: sync reading history, clarified as posts viewed on Substack, saved or not, into the local cache. It distinguishes this from saved-post syncing by emphasizing viewed-but-unsaved posts and their is_saved=0 storage behavior.

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?

Usage is implied by the purpose and by the force parameter explanation, but the description does not explicitly say when to choose this tool versus sync_saved_posts or sync_saved_notes. It gives behavioral context but no direct alternative-selection guidance.

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