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

Annotations already declare readOnly, idempotent, non-destructive. The description adds useful behavioral context beyond them: the full status taxonomy with definitions (e.g., pending_approval = waiting for approval, processing = Instagram still processing video). This is genuinely helpful for interpreting results.

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?

Front-loaded with the core purpose, but the long parenthetical enumerating status meanings is dense and slightly interrupts readability. Every element is relevant, but the structure could be cleaner.

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?

Given no output schema and a simple read-only tool with two well-documented optional params, the description covers purpose, return fields (id, time, platforms, status), and status vocabulary. No output schema exists, so explaining status semantics is a reasonable inclusion that aids result interpretation.

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 fully documents from/to. The description restates them as 'Optional from/to limit the time range' without adding syntax or boundary semantics beyond the schema. Baseline 3 for high-coverage schema.

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?

Specific verb+resource (lists scheduled posts) and enumerates the status values it returns, which helps distinguish it from get_post_status. It doesn't explicitly delineate itself from sibling get_post_status, but the plural 'posts' plus status enumeration makes the distinction reasonably clear.

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 optional from/to parameters imply a time-range listing use case but there's no explicit guidance on when to use this over get_post_status or the filtering tools. Usage is implied by the description rather than stated.

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