Explain ABAP Cloud / RAP release deltas

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

Annotations already declare readOnly/idempotent/closed-world, and the description goes well beyond them: it discloses that the tool does not connect to any SAP system, does not read release notes live, is a curated snapshot dated 2026-09-10, is not a complete changelog, and that the target system's notes remain authoritative. It also describes per-row fields and the meaning of the 'confirmed'/'reported' confidence flag, which the annotations cannot convey.

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?

Purpose, when-to-use, caveats, alternatives and an example are all front-loaded in a logical order, and the example call is a useful close. It is delivered as one dense paragraph, which makes the caveats and sibling pointers slightly harder to scan than bulleted structure would be.

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 5-parameter, zero-required lookup with an output schema, the description supplies everything an agent needs: scope, filter semantics, freshness/curation limits, confidence semantics, sibling routing and a concrete invocation. Return values are covered by the output schema yet are still summarized, leaving no material gap.

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%, so the baseline is 3. The description adds genuine intent beyond the schema: it explains that sinceRelease should be set to the customer's current level to see what an upgrade buys, and it explains why pre-2502 rows exist (to prevent mislabeling established features as novelties). The worked example further clarifies parameter interaction.

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 states a concrete verb ('Look up what changed') and enumerates the exact resource scope (ABAP Cloud, CDS, ABAP SQL, RAP, EML, ABAP Unit, ATC, tooling across named release trains). It explicitly carves out its niche against siblings by pointing to check_released_api and search_sap_knowledge for adjacent questions, so an agent can distinguish it without opening the schema.

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?

It gives explicit when-to-use ('when you are about to write or review ABAP and need to know whether a feature exists in the target release'), concrete trigger scenarios (draft persistence, BUFFER ON, RAP change documents, side effects, feature-control attributes), and named alternatives with their selecting conditions (check_released_api for released-API state, search_sap_knowledge for Clean Core/ATC vocabulary).

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