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

Annotations already declare readOnlyHint=true and idempotentHint=true, covering safety and repeatability. The description adds value by disclosing the return content (title, show, published date, episode ids) and the default behavior when slug is omitted. It does not contradict annotations, and the added details are useful beyond the structured fields.

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 sentences with no filler. The core purpose and the key usage nuance (omitting slug) are front-loaded. Every sentence adds value, making it efficient and easy to parse.

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?

The tool is simple (one optional parameter) and has an output schema to describe return format. The description covers the main behavior, the default case, and the source of the slug parameter. No critical information is missing for an agent to invoke it correctly.

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 input schema covers 100% of the single parameter 'slug' with a description, so the schema already explains its format and optionality. The description repeats the omission behavior but does not add new semantic details beyond the schema. Baseline of 3 is appropriate since schema does the heavy lifting.

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 the tool lists episodes referenced by an edition, specifying the fields (title, show, published date, episode ids). It differentiates from siblings like list_digests (which lists editions) and get_digest (which likely retrieves a single edition) by focusing on episodes. The phrase 'the cheapest way to map a week' adds a clear use-case identity.

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 implies usage context: it is the cheapest way to map a week, and it tells the agent that omitting slug returns the latest edition, which is a practical decision point. It also references list_digests as the source for the slug. However, it does not explicitly compare to alternatives like get_episode or search, so the guidance is implicit rather than fully explicit.

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