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

Annotations already establish readOnly, idempotent, and non-destructive behavior, so the bar is lower. The description adds a genuine behavioral detail beyond the annotations: the return is null when the override is unset, which tells the agent how to interpret an empty result.

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 sentence with the operation and scope front-loaded and the null-case tucked in at the end. No filler or redundancy.

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 no output schema, the description correctly carries the return-value burden by naming what is returned and the unset case. For a simple two-parameter getter this is nearly complete; only the permissions or failure modes are unaddressed.

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%, with both issueId and projectId documented including format examples (SHIP-353). The description adds only the framing that the record is per-issue and per-mission, which the schema already conveys; baseline 3 applies.

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?

Specific verb (Read) plus a precisely named resource (the per-issue agents/baseBranch override record for one mission), scoped to a single mission. It does not name the closely related sibling tools (set_agents_override, clear_agents_override), so an agent must infer the read-vs-write split from the verb alone.

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 implies the usage (fetch the override before acting on it) but never states when to call this versus set_agents_override, clear_agents_override, or get_mission. No prerequisites or exclusions are given; guidance is only inferable.

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