x_post_counts_archive

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

Annotations already declare readOnlyHint and openWorldHint, and the description adds valuable behavioral context: the result contains only counts and ISO timestamps, never post text, making it safe to surface. This goes beyond the annotations by explaining the data-shape guarantee, though it does not cover rate limits or pagination behavior.

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 dense sentences with no filler. The core action, scope, and granularity are front-loaded, followed by safety and use-case context. Every sentence earns its place.

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 an output schema present and all parameters documented in the schema, the description covers the essential selection and invocation context: archive scope, granularity options, safety, and typical use. Minor behavioral details like pagination are left to the schema, which is acceptable.

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%, so the schema already documents all six parameters. The description adds minimal parameter-level value beyond restating granularity and the count-only result; it does not define start_time, end_time, page_token, or raw beyond what the schema provides.

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 uses a specific verb ('Return') and clearly identifies the resource: a volume histogram of post counts for an X v2 query over the complete archive back to 2006. It also states the granularity options, making it immediately distinguishable from sibling tools like x_post_counts_recent and x_search_archive.

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?

It gives a clear use case: gauge volume cheaply before running a full-archive search. It also implies differentiation from recent-count tools by emphasizing 'complete archive back to 2006', but it does not explicitly name alternatives or say when not to use this tool.

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