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

Annotations already establish read-only, idempotent, closed-world behavior, so the description only needs to add context – and it does, by defining 'staleness' (code changed since last analysis) and by disclosing the manual-registration branch of behavior. It could go further on what an 'in-progress ingest' means operationally, but this is solid added value.

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?

Two sentences, front-loaded with the primary read, then the edge case. It is dense but every clause carries information; the only minor cost is that the parenthetical about manual registration is slightly buried mid-sentence.

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 must convey return content, and it does via the enumerated fields plus the no-repository outcome. An agent can call this correctly knowing only legacySystemId; the remaining gap is the format of the returned status values, which is minor.

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?

There is a single required parameter with 100% schema description coverage ('UUID of the legacy system'), so the schema carries the semantics. The description adds nothing about the identifier itself, which is the expected baseline of 3.

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 opens with a specific verb+resource ('Read the connected GitHub repository status for a legacy system') and enumerates exactly what is returned: owner/repo/branch, link status, staleness, in-progress ingest. That is clearly differentiated from siblings like get_legacy_system (system metadata) and trigger_legacy_reanalysis (a mutation).

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?

Usage is only implied: an agent can infer this is the pre-analysis check and that the no-repo case blocks analysis until a human connects a repository. It never names an alternative tool or states an explicit condition such as 'call before trigger_legacy_reanalysis' or 'use get_legacy_system for system metadata'.

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