write_collection_add

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

Annotations already establish that this is a mutating/destructive operation. The description adds valuable behavior beyond that: it appends rather than replaces, which answers a common overwrite concern. It does not cover authorization, return value, or side effects, but the append guarantee is meaningful.

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 dense sentences, with the primary operation and append semantics front-loaded, followed by routing guidance. Every sentence earns its place and there is no filler or repetition.

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 mutation tool with no output schema, the description covers the operation's semantics, the fact that nothing is replaced, and key exclusions, while the schema references read_meta for valid resource and collection names. The phrase 'layer 1' is opaque and not explained, but overall an agent has enough context to call this correctly.

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?

The schema already documents resource, collection, and items with examples, covering 75% of parameters. The description itself adds little per-parameter detail, and the id parameter remains undocumented. This is an acceptable baseline because the schema carries most of the burden.

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 action ('Add items') with a clear target ('an addable collection of an entity') and the key semantic detail that posts APPEND without replacing. It also distinguishes itself from siblings like write_assign, write_team, and write_set_role_effort by naming them directly.

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?

Explicitly tells agents when not to use this tool: for assignments, teams, and role efforts, prefer write_assign, write_team, and write_set_role_effort. This is clear routing guidance that helps an agent choose the correct sibling without opening their schemas.

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