list_posts

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

With no annotations, the description carries the full burden of behavioral disclosure. It clearly states the key behavioral traits: results are slim indexes, full content is excluded, and records include a 150-char snippet. It also frames the operation as non-destructive and efficient. It does not mention ordering or pagination, but for a read-only list tool with a defined limit parameter, the disclosed behavior is sufficient.

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 compact and front-loaded: the first sentence states purpose and output scope, the second provides usage guidance, and the third gives the efficiency rationale. The Args block is structured and every line adds necessary semantics. There is no filler or redundancy.

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?

The description covers the tool's purpose, the relevant sibling flow, all parameter semantics, and the critical output difference from get_posts(). Since an output schema exists, the exact return fields do not need to be restated. The description is complete enough for an agent to select and invoke the tool correctly.

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?

The input schema provides only type/default information and has 0% description coverage, so the parameter descriptions carry the full burden. The Args section adds rich meaning: account accepts a slug or URL, empty means all accounts and points to list_accounts(), category is a semantic filter, days_ago has a clear meaning, and limit gets default/max constraints. This fully compensates for the schema's lack of descriptions.

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 opens with a specific verb and resource: 'Return a slim index of posts.' It explicitly distinguishes the tool by noting it returns 'metadata + 150-char snippet, NO full content' and frames it as the survey-before-reading counterpart to get_posts(). This leaves no ambiguity about what the tool does.

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 gives a clear usage scenario: 'Use this to survey what posts exist before deciding which ones to read in full via get_posts().' It also explains why this path is preferable ('Fetching slim records first is far more token-efficient'), which helps the agent choose it over get_posts().

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