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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is covered. The description adds the dual addressing mode (id or 0-based index), which is useful behavioral detail, but says nothing about lookup failure behavior or return size/shape.

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, no filler, with the core action stated first and the addressing rule immediately after. Every clause carries information.

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?

For a read-only, idempotent, two-parameter tool with full schema coverage and no output schema, the description covers purpose and phase addressing adequately. It stops short of noting what happens for an unknown phase id or out-of-range index.

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 already 100%, so baseline is 3, but the description adds meaning beyond the schema by specifying that index addressing is 0-based and counted among *authored* phases, resolving an ambiguity the schema's generic 'index' example leaves open.

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 (load) and resource (methodology content for one phase of a skill), and the phrase 'one phase' implicitly separates it from the whole-skill sibling get_skill. It does not explicitly name siblings, but the granularity is clear from the text.

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 by the phrase 'one phase of a skill' – an agent can infer that this is the choice when a single phase is needed rather than the full skill. There is no explicit when-to-use, when-not-to-use, or named alternative among get_skill/list_skills.

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