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

No annotations are provided, so the description must carry behavioral context. 'Load' implies a read operation, and the description clarifies the webhook-reply scenario, but it does not disclose pagination behavior, authentication needs, or return format. This is adequate but not rich.

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 no filler. The core purpose is front-loaded, the exclusion is stated next, and the parameter rule is given last. Every sentence earns its place.

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?

The description is sufficient to make a basic call, but with no annotations and no output schema, the agent is left without guidance on token usage, pagination, or what the thread history response contains. These are notable gaps for a 4-parameter 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 only 25%, but the description adds meaningful semantics by explaining the OR relationship between peer and thread_id. However, token and limit are left unexplained beyond their schema metadata, so the description only partially compensates for the low coverage.

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 begins with a specific verb and resource: 'Load thread history.' It also distinguishes this tool from the reply path by stating a webhook reply should use reply_in_reply_to instead, making its purpose clear and differentiated.

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?

The description explicitly tells the agent when not to use this tool ('A webhook reply does not need this') and names the alternative ('use reply_in_reply_to from the wake body'). It also gives a direct invocation rule: 'Pass peer=their handle OR thread_id.'

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