messages_recent

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

No annotations are provided, so the description carries the full behavioral burden. It correctly frames this as a plain recency retrieval with no semantic ranking, but it does not disclose result ordering guarantees beyond "most recent", pagination behavior, or whether defaults are applied server-side. Adequate but with clear gaps for a zero-annotation tool.

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?

Two compact sentences with the core purpose front-loaded and the routing cues immediately after. There is no filler and every clause earns its place.

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?

For a two-parameter, no-output-schema read tool with fully documented parameters, the description covers what an agent needs in order to call it correctly. It could be slightly more complete by pointing to the sibling to use when filtering by contact or thread is needed, which is the only real gap.

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 two parameters (limit, days_back) and their defaults are already fully documented in the schema. The description adds the recency framing but no additional syntax or format detail beyond what the schema provides, so the baseline of 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?

The description states a specific verb and resource ("Get most recent messages") and explicitly scopes it against the semantic-search alternative ("without semantic search"), which distinguishes it from siblings like messages_search and smart_search. An agent can tell what this does and how it differs from the search tools without opening any 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?

It gives concrete trigger conditions with quoted user phrasings ("recent messages", "latest texts", "what messages did I get"), which is strong when-to-use guidance. It stops short of naming the sibling to use instead for filtered/lookup cases, so it is clear context but not a full use-this-not-that rule.

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