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

No annotations exist, so the description carries the full burden. It discloses that the tool is free and implicitly read-only ('get', 'poll'), and hints at delta-vs-state semantics, but says nothing about auth, rate limits, pagination, or the return item shape. Useful but incomplete for an unannotated 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?

Three short sentences with the cost signal ('Free') front-loaded, then content, then usage. Every sentence earns its place and nothing is padding.

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 single-parameter read tool with no output schema this covers the essentials of what comes back and how to call it repeatedly. It still leaves gaps on item structure and on how 'limit' affects the delta window, which matter for correct invocation.

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?

The single optional 'limit' parameter has 0% schema description coverage and the description never mentions it. With low coverage the description is expected to compensate, but it provides no guidance on bounding (1-100) or default behavior.

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 (a feed of recent items) and enumerates the kinds of events returned: new probed providers, price moves, crossed markets, releases. That makes it distinguishable from siblings like get_market or get_pulse. It doesn't explicitly name which sibling to use for market snapshots vs. event streams, so it stops short of a 5.

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?

'Poll for what changed since last time' gives a genuine usage pattern: repeated polling for deltas. However, it gives no when-not guidance and never names alternatives (e.g., get_pulse or get_market) that an agent should pick when it wants a snapshot rather than a delta stream.

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