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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so safety needs no restating. The description adds genuine behavioral facts beyond them: results exclude post text, pagination defaults to size=10 with max=100, and the platform constraint is per-call. Return shape is not described, but an output schema exists, so that gap is minor.

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?

Five tight sentences, front-loaded with what the tool returns, then the exclusion, then the prerequisites and call-cardinality constraint. Every sentence carries information an agent needs to call it correctly; nothing is padding.

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?

Covers the non-obvious pieces for a filtered list tool: required scope, where account_id comes from, that post text is elsewhere, per-platform call cardinality, and page-size limits. The output schema relieves the description of explaining return structure.

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?

Adds meaning the schema cannot: account_id must come from postey://accounts and should never be guessed, and platform is required per call. However it omits the tag_id and page filters entirely, and its status list (DRAFT, SCHEDULED, PUBLISHED) is missing PUBLISHING, which the schema enum includes — an agent reading only the description would not know that state exists.

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 post summaries') plus the mandatory scope: one account and one platform, filtered by status. The status values are named, so an agent can distinguish this from get_post_content or get_platform_comments without opening the 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 triggers ('my posts', 'drafts', picking a post) and an explicit alternative for the case this tool does not serve ('postey://posts/{post_id}/content/{platform} has that'). It also warns that a cross-platform question requires one call per platform, which heads off a common mis-call.

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