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

Annotations already establish readOnly, idempotent, non-destructive, and closed-world behavior, so the safety profile is covered. The description adds genuine behavioral context beyond them: the call-frequency expectation ('ONCE at the start') and the structure of what is returned (roster first, then handoffs). No pagination or size cues, so not a 5.

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?

One sentence, front-loaded with the imperative action timing, no filler. Every clause (once, start of session, cross-project scope, return contents) carries distinct information.

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?

There is no output schema, so the description must carry return-value context, and it does describe the opening roster and handoffs. 'What happened recently' remains slightly abstract about the full range of returned activity, keeping this just short of complete.

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 the single 'days' parameter is fully documented in the schema (range 1-30, default 2, when to increase). The description adds nothing about the parameter, so the baseline 3 is appropriate.

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 action (catch up on what happened) with an explicit cross-project scope, and even previews the return shape (project roster with slug and purpose, plus open handoffs). That scope distinguishes it from narrower siblings like arroway_read, arroway_search_log, or arroway_continue without needing to name them.

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 a clear usage condition and timing constraint: 'Call ONCE at the START of a session, before there is a task.' This implicitly excludes mid-task use and repeated calls. It stops short of naming an alternative sibling or an explicit when-not, so it is clear context rather than full routing guidance.

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