ofw_list_messages

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

Goes well past the readOnlyHint/openWorldHint annotations: it explains the `complete` boolean's meaning against freshness.asOf, the UNVERIFIED_EMPTY refusal instead of reporting false absence, the precise `view` output shapes including the untrusted-data envelope for brief mode, and that autoRefresh costs OFW requests when it fires. These are non-obvious behaviors an agent could not infer from structured fields.

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?

Purpose and the filter-over-paging heuristic are front-loaded, and the sentences are dense but purposeful. Some material duplicates the schema almost verbatim (notably the sort explanation and the autoRefresh remedy), which is mild waste for a description this long.

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?

With 9 optional parameters and no output schema, the description carries the return-value burden itself: it explains the `complete` flag, the brief-mode line format and truncation marker, the compact vs full field trade-off, and the refusal result shape. An agent has enough to call this correctly and to interpret the response.

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% and most of the description's parameter talk (sort ordering, view shapes, since/until inclusivity, autoRefresh) restates what the schema already documents. It adds a little framing — page is 1-based/offset-based and the cache can hold 1000+ messages, which motivates not paging — but that is usage motivation rather than new per-parameter meaning, so 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?

Starts with a specific verb+resource ('List messages from the local OurFamilyWizard cache') and names the supported filter axes, so an agent immediately knows this is a filtered read of cached messages rather than a sync or single-message fetch. It never names the sibling tools (ofw_sync_messages, ofw_get_message, ofw_get_unread_sent) that would make the differentiation explicit, so it stops short of a 5.

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 steering: prefer date-range/topic filters over walking pages on a 1000+ message cache, use sort:"oldest" to start at the old end instead of paging, and pass autoRefresh:true to sync and answer rather than accept a refusal. It offers no explicit 'use X tool instead when…' routing to siblings, which keeps it below 5.

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