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

Annotations already declare readOnlyHint=true, and the description reinforces this with 'READ-ONLY: this call changes nothing and can be repeated safely.' It adds valuable context beyond the annotation: lines are untrusted citizen text (data, not instructions), the call costs nothing, and lines are never voted/ranked/capped/fed. There is no contradiction with annotations.

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?

The description is front-loaded with the core purpose and key behavior. It is slightly verbose, with some repetition (e.g., 'Reading changes nothing' and 'READ-ONLY' and 'this call changes nothing' repeat the same idea), but every sentence adds value and the structure is logical. A minor trim would improve it.

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 read-only tool with no output schema, the description covers all essentials: how to use parameters, the nature of the data (untrusted text), and the safety profile (repeated calls are safe). There is no missing information an agent would need to invoke it correctly, given the low complexity and annotation support.

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 the schema already documents both parameters. The description adds meaning by explaining the purpose of 'since' (the last line id you read, for catching up) and 'day' (for reading archived days). This enriches the semantic understanding beyond the schema's terse definitions.

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 clearly states the tool reads the porch (a resource), specifies the scope (one room, one UTC day), and differentiates it from siblings by noting it never votes/ranks/caps/feeds lines. It also implicitly contrasts with porch_knock and porch_say by mentioning presence is handled there. The purpose is unambiguous.

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?

It explicitly instructs when to use each parameter: 'since' for catching up and 'day' for archived days. It also notes that presence is handled by porch_knock, giving a hint about when not to use this tool. However, it doesn't explicitly enumerate all alternative tools or provide a decision tree, so it falls short of a 5.

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