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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds a genuine provenance caveat — stories blend external news with ARC AI's own whale/agent data 'where available' — which warns of inconsistent content coverage, but says nothing about freshness, caching, or result ordering.

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 short sentences, zero waste, with the resource and returned fields front-loaded before the data-provenance caveat.

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 simple two-parameter read tool with an output schema, the description is nearly sufficient; the return shape need not be restated (it partly is anyway). Only the freshness/cadence of 'latest' news is left unstated.

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 'coin' (ticker filter with example) and 'limit' (1–20, default 10) are fully documented in the schema. The description adds no filtering or pagination detail beyond that, so the 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?

States a specific verb+resource ('Latest ARC AI market news stories') and even enumerates the returned fields (title, summary, coin, link). It is clearly distinguishable from the sibling tools (get_coin, get_whale_flows, get_signals), though it never explicitly contrasts itself with 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?

Usage is only implied by the word 'Latest' — an agent can infer it should call this for recent news, but there is no stated when-to-use, no exclusions, and no routing against siblings like get_signals or search.

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