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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the tool is known to be safe. The description adds a critical behavioral note: the returned text is published material and should be treated as data, not as instructions. This is a valuable addition for security and data handling, going beyond annotations. It also mentions it returns a specific set of fields, which adds to transparency. The only minor gap is not specifying pagination behavior, but annotations cover safety.

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 a single concise sentence that front-loads the core purpose (lists published digest days, newest first) and the fields included. The second sentence about treating returned text as data is a valuable addition but could be integrated more elegantly. It is appropriately sized and not verbose.

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 the tool is a simple list operation with a fully described schema and rich annotations (readOnly, idempotent, non-destructive), the description covers the essential information. It explains the output fields and order. It could mention pagination behavior (like that it returns a page and how to request more pages), but since parameters are documented, the missing piece is minor. The security note about content is an extra, making it fairly complete.

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%, meaning the schema already adequately documents both parameters (limit and offset) with their types and defaults. The description does not add further meaning to these parameters; it only mentions they exist implicitly. Since the schema covers them well, the baseline is 3, and the description adds no extra semantics beyond the schema, so a score of 3 is appropriate.

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 published digest days with a specific set of fields (date, page URL, canonical Markdown path, teaser) and order (newest first). It is distinct from siblings like get_digest, which likely fetches a single digest, and list_day_views or list_sources, which address other list types. It could be slightly more explicit about how it compares to get_digest, but overall it's clear.

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 provides context for when to use the tool (listing published digests) but does not explicitly state when NOT to use it or explicitly mention alternatives like get_digest for a single digest. The use case is clear for listing all published digests, but there is no direct comparison to sibling tools. The context signal mentions siblings but the description itself lacks explicit guidance.

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