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

Annotations cover the read-only/non-destructive profile, and the description adds real operational detail beyond that: newest-import-first ordering, the fact that dates are import time rather than original save time, that calls count toward account usage, and that they appear in the user's activity log. The import-time caveat is exactly the kind of subtle behavior an agent would otherwise misreport.

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 action and scope, then the caveat, then the operational note. Four sentences with little waste, though 'Returns up to limit results' largely duplicates the schema's maximum of 50.

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?

No output schema exists, so the description carries the return-value burden; 'list posts ... newest imports first' plus the cap gives an adequate picture of the result shape and ordering. It stops short of describing what a post record contains, but that is a minor gap for a simple listing tool.

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 days, limit, and the platform enum are already fully documented with ranges and defaults. The description only restates the day window and result cap and says nothing about platform filtering semantics, so the baseline 3 applies.

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 imported into the authenticated user's AgentMash library') plus scope ('last N days, newest imports first'). An agent can tell it apart from get_save or list_collections, but the sibling most likely to be confused with it, search_saves, is never named or contrasted.

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?

'Use for a recent library recap' gives a clear use context, and the import-time caveat hints at when this differs from a plain save-date listing. However, there are no explicit exclusions or named alternatives such as search_saves for filtered lookups.

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