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

Annotations only declare read-only and non-destructive; the description adds the crucial behavioral facts an agent needs: no date filter (must page and read timestamps), ordering (newest first), and the full semantics of each status including the Instagram hourly cap and monthly plan limit. This is well beyond annotation coverage.

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 resource and row shape, then the status glossary, then the routing advice. Dense but every sentence carries information; the status enumeration is long but genuinely needed because the enum values are opaque.

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 no output schema, the description takes on the burden of describing the returned columns (time, campaign, handle, comment, keyword, outcome) and it does so fully, plus covers the filtering limitation and the alternative tool. Nothing an agent needs is missing.

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 coverage is 100%, so baseline is 3, but the description goes further by explaining the meaning behind status values (SKIPPED_DEDUP, SKIPPED_PLAN_LIMIT, etc.) and the absence of a date filter, which changes how page/limit must be used. It stops short of explaining page/limit interplay explicitly since the schema already covers those.

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 resource (the send log) with explicit shape ('one row per comment or message HookSend acted on') and enumerates the returned fields. An agent can immediately tell this apart from stats_overview, leads_recent, and guard_recent_decisions.

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?

Names two concrete use cases ('check whether something is actually being delivered', 'explain a particular failure'), states the limitation ('there is no date filter'), and routes to the alternative ('for weekly and monthly totals use stats_overview instead'). Full when/when-not/alternative coverage.

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