get_state

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

Despite no annotations, the description discloses read-only nature, return fields, and the fact that data is cached (avoiding API calls). This covers key behavioral traits.

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?

Two short paragraphs, each sentence earns its place. No fluff, front-loaded with purpose and key details.

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?

With one optional parameter and no output schema, the description adequately explains input semantics and output content. Could mention potential size of results, but not necessary for this single-param tool.

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 sole parameter channel_ids is clearly explained: if provided, filter to those channels; otherwise return all. Schema only has type info, so description adds essential meaning.

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 'read-only view of the discovery state file' and specifies the returned fields (video_id, published_at, analyzed_at). It distinguishes from sibling tools like list_tracked_channels by focusing on state per channel.

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?

Explicitly mentions it is useful for answering 'what's the latest video I've seen from channel X?' without re-hitting YouTube, providing clear context. Does not explicitly mention when not to use, but the purpose is well-scoped.

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