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

Adds substantial behavior beyond the annotations: the 5,000-indicator cap, the 1–7 day bound, a 10-minute cache, no-auth public read, and the fact that the full bundle lives at bundle_url and requires an API key. It also discloses edge behavior (feeds like Spamhaus DROP label by list rather than family; countries only present when records carry one), which the readOnly/idempotent annotations cannot convey.

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 purpose and return shape before caveats, and every paragraph is structurally distinct. There is some redundancy — SIEM ingestion planning is mentioned twice and the example sentence repeats capacity-planning framing already stated above.

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 burden of explaining return contents, and it does so exhaustively (counts, top families/labels, top feeds, type breakdown, countries, bundle_url). Auth, caching, and cap constraints are all covered for a single-parameter read 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 coverage is 100% (min 1, max 7, default 1), so the baseline is 3, but the description adds meaning the schema does not: how the window interacts with the 5,000 cap, and a worked example `{"days": 7}`. Marginal but genuine added value over the schema.

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?

Opens with a specific verb and resource ("summarizes what is in the feed right now") and then enumerates exactly what the report contains: counts in window, top malware families or list labels, top source feeds, indicator-type breakdown, and top countries. It also explicitly distinguishes itself from the full STIX bundle, so an agent knows this is an aggregate view, not the data pull.

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 conditions ("what's active this week", feed freshness, planning SIEM/blocklist ingestion, checking a campaign is in the corpus) and names the alternative it precedes ("use before pulling the full STIX bundle"). It does not differentiate against the listed sibling tools such as enrich-ioc, correlate, or search, so routing between those is left to inference.

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