get_post_counts

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

With no annotations, the description must carry the behavioral burden, and it does disclose two non-obvious traits: full_archive=True 'requires archive access' (a permission prerequisite) and the default False path only covers 'the last 7 days' (a silent scope limitation). It stops short of covering rate limits or result shape, but the access requirement and default window are exactly the kind of hidden behavior an agent needs.

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 purpose is front-loaded in sentence one, followed by a clean Args block that maps one line per parameter with no redundancy. The format is efficient, though the multi-line indentation is slightly heavier than a compact prose description would be.

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 5-parameter tool with an output schema (so return values needn't be explained), the description covers formats, defaults, enums, and the archive-access prerequisite. The only real omission is explicit routing against the search_full_archive_posts sibling, which would help disambiguate the two archive-capable tools.

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 0%, so the description must compensate entirely, and it does: it documents all five parameters, gives granularity's allowed values ('day', 'hour', 'minute') and default, specifies ISO 8601 UTC format with a concrete example timestamp, and explains the semantic difference between the two full_archive modes. This is meaning well beyond the bare schema types.

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 opening sentence states a specific verb and resource ('Analyze post volume and trend counts on X') and explicitly carves out the boundary 'without fetching individual posts,' which distinguishes it from search_recent_posts, search_full_archive_posts, and get_post. An agent can select this tool over its siblings without opening any schema.

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 phrase 'without fetching individual posts' implies when this tool is preferable to the search siblings, and the full_archive/default-7-days note gives context for the two query modes. However, no sibling tool is named and there is no explicit 'use this when / use X instead' routing, so usage remains inferred rather than stated.

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