Get Message Context

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety and scope are covered. The description adds the useful behavioral fact that output is a windowed set of neighboring messages, but says nothing about the radius default/cap (10, max 50) or how the window behaves at chat boundaries.

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?

A single front-loaded sentence with no filler; the core behavior comes first and the example follows. Slightly fragmentary parenthetical, but nothing is wasted.

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?

With an output schema present and a simple three-parameter surface, the description covers what the tool returns at a conceptual level. The main omission is any mention of the radius parameter's effect, which an agent would otherwise have to infer from the schema alone.

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 67%: chat and radius are documented inline, only message_id lacks a description (though it is self-evident). The description adds no meaning beyond the schema — it does not mention that 'radius' controls the window size, which is the one parameter whose semantics matter most here.

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 ('Show') and a clearly defined resource: a message plus its surrounding messages. The parenthetical 'e.g. after a search hit' implicitly distinguishes it from the plain message fetch sibling, though it does not name a sibling explicitly.

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 phrase 'after a search hit' gives one concrete usage scenario, which is useful implied guidance. However, it never names an alternative (e.g. get_messages or search_messages) or states when this tool should not be used instead of them.

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