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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint=false, so the safety profile is covered. The description adds value beyond that with the newest-first ordering guarantee and the warning that busy workspaces hold hundreds of posts (implying cost/latency and the need to filter). It stops short of describing pagination or a cursor, so it is not a 5.

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?

Four sentences, all load-bearing: scope/ordering, use cases, filtering advice, and sibling routing. The primary purpose is front-loaded. Slightly dense in the second sentence, where three use cases are packed into one clause chain.

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 two-parameter read tool with no output schema, the description covers ordering, volume expectations, and how to locate a post's id for follow-up mutations. It does not sketch the returned fields, but the annotations carry the safety profile and the schema carries the inputs, so nothing critical is missing.

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 coverage is 100%, so both parameters are already documented; baseline 3 applies. The description's 'filter by status and keep the limit small' adds mild practical guidance, but it also lists 'published' where the schema enum says 'posted', a small terminology mismatch that could confuse an agent.

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?

States a specific verb and resource (list posts) plus scope (this workspace), ordering (newest first), and the full set of statuses covered. It explicitly distinguishes itself from get_post, get_performance, and list_evergreen, so an agent can route without opening another 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?

Gives concrete when-to-use triggers: check what exists before writing, find an id to pass to update_post or cancel_post, or answer a scheduling question. It also names the alternatives for the adjacent needs (single post, metrics, evergreen library), which is exactly the routing information an agent needs.

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