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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description does add one real piece of context beyond that: the replay is 'rebuilt from its record,' implying a materialized/historical artifact rather than live state. It stops short of saying whether the replay is complete, cached, or how large it can be.

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 tight sentence with no filler, and the framing ('every step of a session') is front-loaded. It is arguably too terse for a tool with no output schema, but nothing in it is wasted or padded.

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?

There is no output schema, so the description carries the burden of explaining what comes back — and it does not, beyond the vague 'spectator view.' An agent cannot tell whether it receives a step list, a rendered frame sequence, or a single object, nor how this differs from get_session.

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 100% and the schema itself documents session_id as coming from start_game, so the parameter is well covered without the description. The description adds nothing about the parameter, which is acceptable given full schema coverage but earns only the baseline.

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 sentence conveys that the tool reconstructs a session step-by-step from its stored record, which is more specific than restating the title. But it never uses a verb like 'get'/'return' and never names the resource as a replay artifact, so an agent must infer that the output is a replay rather than live state. It also gives no differentiation from the sibling get_session, which is the obvious confusion point.

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?

There is no guidance on when to call this instead of get_session, get_game, or get_agent, all of which live in the same session domain. No prerequisites, no conditions, no exclusions are stated; the only hint is the phrase 'spectator view,' which is never explained.

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